"NicolaeTestemitanu"StateUniversityofMedicineandPharmacy

ChairofBiochemistryandClinicalBiochemistry

STRUCTURALBIOCHEMISTRY

PracticalguideforFacultyofDentistrystudents

Student_________________________

Groupnr.______________________

Professor________________________

CHISINAU,2018

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LESSON№1 Data_________________

Introduction.Theimportanceofbiochemistryformedicine.Bioelementsandbiomolecules.Functionalgroupsandtypesofchemicalbondsspecificforbiomolecules

TheInitiallevelofknowledge

1. Chemicalelements.Periodictableofchemicalelements.

Self‐trainingquestionsIssuesfortraining1. Introductiontobiochemistry.Theimportanceofbiochemistryformedicaldisciplines.

Structuralbiochemistryanditsgoals.2. Bioelements ‒ organogenic and minerals. Content and overview of the main

bioelementsthatmakeupthehumanbody.3. Biomolecules.Micromolecules,macromoleculesandcomplexmolecules.4. Functionalgroups.Typesoffunctionalgroupsspecificforbiomolecules.Theirgeneral

properties.5. Typesofchemicalbondsspecificforbiomolecules.Theirgeneralproperties.

Tasksforindividualwork1. Carbon in the unexcited state has the electronic configuration of the outer level

(valencelevel)2s22p2andinthecompoundsitcanhavethedegreeofoxidation+2,but in the excited state it has the electronic configuration 2s12p3. How canschematicallybeshowntheelectrontransition?

2. DrawtheschemeofelectronicinteractionofammoniawithH+ionbydonor‐acceptor

mechanism.

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3. Placethemoleculeintothespecificcolumnofthetableaccordingtothechemicalbondpresentinthemolecule–CO2,H2O,HCl,NH4,O2,N2,Cl2,CH4,NaCl,NaH2PO4,Na2CO3,protein,DNA.

Covalentnon‐polar Covalentpolar Ionic Hydrogen

Self‐assessmenttests:

1.Whichofthefunctionalgroupsdeterminestheacidicpropertiesofbiomolecules?

a)–SH; b)–NH2; c)–CONH2; d)–COOH; e)–OH2.Whichofthefunctionalgroupsdeterminesbasicpropertiesofbiomolecules?

a)–SH; b)–NH2; c)–CONH2; d)–COOH; e)–OH3.Whichtypeofbondisproducedbetweentheatomsofthesamekindorbetweentheatomswithsimilarelectronegativity?

a) covalentpolar;b) hydrophobic;

c) covalentnon‐polar;d) donor‐acceptor;

e) coordinative

4.Whichtypeofbondisproducedbetweendifferentatomsofnon‐metallicelementshavingdifferentelectronegativity?

a) covalentpolar;b) ionic;

c) covalentnon‐polar;d) donor‐acceptor;

e) coordinative

5.Whatkindofchemicalbondisformedasaresultofammoniainteractionwithhydrogencations?

a) covalentpolar;b) ionic;

c) covalentnon‐polar;d) donor‐acceptor;

e) hydrogenbond

6.SelectthecorrectstatementsregardingVanderWaalsforces:

a) relativelyweakforcesofattractionbetweenneutralmolecules;b) relativelyweakforcesofrejectionbetweenneutralmolecules;c) forcesofstrongattractionbetweenneutralmolecules;d) forcesthatstabilizethepolarcovalentbonds;e) forcesthatstabilizethenon‐polarcovalentbonds.

7.Whichpairsofatomsandfunctionalgroupswillformionicbonds?

a) CandN;b) NH2andH+;

c) COO‐andNH3+;d) Cl‐andNa+;

e) COO‐andNH2.

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8.Hydrogenbondisformedbetween:a) apartiallypositivelychargedhydrogenatomandpartiallynegativelychargedO,NorSb) apartiallynegativelychargedhydrogenatomandpartiallypositivelychargedO,NorSc) apositivelychargedhydrogenionandpartiallynegativelychargedO,NorSd) apartiallypositivelychargedhydrogenatomandpartiallynegativelychargedO,NorPe) apositivelychargedhydrogenionandnegativelychargedOorN.

LESSON№2 Data_________________

Waterstructure,physicalproperties,ionization,ionicproductandpH.Buffersolutions

Experiment1.PreparationofbuffersolutionsTask.Prepare20mlof0.1mol/laceticbufferwithpH=5.24using0.1mol/lCH3COOHand0.1mol/lCH3COONasolutions.Dissociationconstantofaceticacidis3∙10‐5.Background. Buffer solutions can be prepared in two ways: 1) solutions of eachcomponentsarepreparedseparatelyandafteraremixedinone,2.)onecomponentofthebuffer solution is dissolved in water and another component is added to the obtainedsolution.ItisimportanttoknowthevalueofbuffersolutionpKaandtocalculatesolutionpHusingHenderson–Hasselbalchequation.Procedure1. Calculate howmanymilliliters of 0.1 mol/l CH3COONa and 0.1mol/l CH3COOH are

necessarytomixtoobtain20ml0.1mol/lofaceticbufferwithpH=5.24.2. CalculatetheratioofcomponentsusingtheequationрН=рКа+lg[salt]/[acid].3. Fromtheratioofbuffermixturecomponents results that it shouldcontainXpartsof

saltandYofacid, i.e. all4parts.So, thesaltvolume isequal to (20•x) :4,andacidvolumeisequalto(20•y):4.

4. CheckthepHofthepreparedbuffersolutionusinguniversalindicatorpaperstripsorthepH‐meter.

5. Thereportmustcontainthecalculationoftheratioofthemixturebuffercomponents.6. Fillinthetable:

Theratioofthemixturebuffercomponents

AcidVaandsaltVsvalues

pHvalue

Conclusion

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Experiment2.Determinationofbloodserumbuffercapacity.Procedure.5mlofbloodserumwithpH=7.4areaddedtotwotest‐tubes.Inonetest‐tubeareadded5dropsofphenolphthaleinandsolutionistitratedwith0.1mol/lNaOHtilltheappearanceof thesamecolorascolorofreferencesolutionthathaspH=9.4. Inanothertest‐tube methyl orange is added and solution is titrated with 0.1 mol/l HCl till theappearanceofthesamecolorascolorofreferencesolutionthathaspH=3.4.

Thenthebuffercapacityiscalculatedbyacidandbybasewithequations(1)and(2).

(1)

(2)where:Вb–buffercapacitybybase;

Вa–buffercapacitybyacid;n(HCl),n(NaOH)–quantityofaddedacidorbaseto1lbuffersolution.рН1andрНs–initialandfinalvaluesofpH(tilltitrationandaftertitration).Vs–thevolumeofbloodserum;V(NaOH),V(HCl)–thevolumesofbaseandacidusedfortitration,c(NaOH),c(HCl)–theconcentrationofbaseandacidconsumedduringtitration.

In the conclusion compare the buffer capacity of blood serum by acid and by base andexplainwhythebuffercapacitybyacidisgreaterthanthecapacitybybase.Results:

Conclusion:

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Self‐trainingquestions1. Theoryofsolutions.2. Water–physicalandchemicalproperties,roleinthelivingorganisms.3. Electrolyticdissociationtheory–basicconcepts.4. ThemainconceptsofBronsted‐Lowryprotolytictheoryofacidsandbases.5. Waterdissociation.Theionicproductofwater.6. ThenotionofpH.Solution’spHandpOHmethodsofdetermination.7. The buffer solutions. Principles of buffering. Henderson‐Hasselbalch equation. Buffer

capacity.8. BodyliquidspHlevel.Biologicbuffersystems.

Casestudy

1. Show the composition and themechanism of action of the phosphate buffer systemafteradditionofsmallamountsofstrongacidsorbases.ThepHequationofphosphatebuffer.

2. The content of hydrochloric acid ranges from 0.07 to 0.15% in normal gastric juiceCalculatetherangeofpHchangeignoringtheinteractionforcesbetweentheН+andCl¯ions. C

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3. TochangethepHof100mlbloodfrom7.36to7.0isnecessarytoadd36ml0.05mol/lHClsol.Calculatebuffercapacityoftheblood.

Self‐assessmenttests

1.What abnormal physical properties ofwater are essential for a normal functioning ofhumanorganism?

a) lowboilingpoint;b) highboilingpoint;c) bigheatcapacity;

d) lowheatcapacity;e) highpermittivity

2.Atomsofwhichelementsincompoundscanformhydrogenbondswithhydrogen?

a) carbon;b) sulfur;

c) phosphorus;d) oxygen;

e) nitrogen

3.Whatmixturesfromthelistedbelowareconsideredbuffersystems?

a) sulfuricacid+sodiumsulphate/H2SO4+Na2SO4;b) carbonicacid+sodiumbicarbonate/H2CO3+NaHCO3;c) aceticacid+sodiumacetate/CH3COOH+CH3COONa;d) aceticacid+ammoniumacetate/CH3COOH+CH3COONH4;e) sodiumdihydrogenphosphate+disodiumhydrogenphosphate/NaH2PO4+Na2HPO4

4.Whatfactorsaffectbuffercapacity?

a) thecomponentsofbuffersystem;b) thestrengthofacidsandbases;c) thevaluesofрКаandрКbofweakacidsandbases;d) thecomponentsconcentrationandtheirratio;e) thepHofbuffersystem.

5.Themainbloodbuffersystemsare:

a) hemoglobin–oxyhemoglobin;b) ammoniabuffersystem;c) hydrogencarbonatebuffersystem;d) phosphatebuffersystem;e) aminoacidbuffersystem.

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6.Select thecorrect statementsconsidering the following two solutions:A. bufferwithH2PO4–=0,1M,HPO42–=0,2M;B.bufferwithH2PO4–=0,15M,HPO42–=0,3M.

a) solutionAhasahigherpH;b) solutionBhasahigherpH;c) bothsolutionhavethesamepH;d) solutionAhasahighercapacity;e) solutionBhasahighercapacity.

7.SupposeweprepareabufferwithanacidHA,thathasthepKaof5.What is thepHwhen[A–]/[AH]=10?a) 1; b) 2; c) 3; d) 4; e) 5.

LESSON№3 Data_________________

Aminoacids–structure,classificationandbiomedicalimportance.

Primarystructureoftheproteins

Experiment №1. Identification of amino acids that contained weak‐bonded sulfur (Folreaction)Method'sprinciple:Weakly bonded sulfur fromproteins and peptides is eliminated byNaOHintheformofNa2S,whichinteractswithNa2PbO2toforminsolublePbS(darkbrownorblackprecipitate).

Note:FolreactionisnegativeforMetwhichcontainedstabile‐bondedsulfur.Procedure:Mixthereagentsaccordingtothetable.

Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

№ Reagents Testtube1 Ovalbumine1% 5drops2 Folreagent 5drops

Boilthesolutionfor1‐2min

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Experiment№2.XantoproteicreactionMethod'sprinciple:AromaticaminoacidsarenitratedwhileboilingwithHNO3and thesolutioncolorternsyellow.Additionofalkalichangethecolorinorange.

Procedure:

№ Reagents Testtube1 Ovalbumine1% 5drops2 HNO3concentrated 5dropsBoilafewminutesCoolthesolution3 NaOH20% 10drops

Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment№3.NinhydrinreactionMethod'sprinciple:Ninhydrinreactswith‐aminogroupsofaminoacidsandproteinstoformablue‐violetcompound.

Procedure:Mixthereagentsaccordingtothetable.

№ Reagents Testtube1 Ovalbumine1% 5drops2 Ninhydrine0,5% 5dropsBoilthesolutionfor1‐2min

Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

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Experiment№4.BiuretreactionMethod's principle: Peptidic bonds react with CuSO4 in alkaline conditions to formcomplexcompoundscoloredinred‐violet

Procedure:

№ Reagents Testtube1 Ovalbumine1% 5drops2 NaOH10% 5drops3 CuSO41% 2dropsShakethoroughly

Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

Self‐trainingquestions:1. Aminoacids–roleinthelivingorganism.Proteinogenicandnon‐proteinogenicamino

acids.2. Classification of amino acids according to their chemical structure, physico‐chemical

andacid‐baseproperties.3. Aminoacidsproperties–stereoisomery,solubility,acid‐baseproperties.4. Chemical properties of amino acids – reactions of carboxylation, decarboxylation,

hydroxylation,deaminoationandtransamination.5. Polypeptidetheoryoftheproteinstructure.Peptidebondproperties.Nameandreading

theaminoacidsinpeptidesandproteins.N‐andC‐terminalaminoacids.6. Methodsfordeterminationofaminoacidcompositionandsequenceinthepolypeptide

chain.

Casestudy:1. Divide the following amino acids in groups according to the biological classification:

Thr,Cys,Phe,Gln,His,Met,Gly,Arg.Writeapeptide that consistsof essential aminoacids.Givethedefinitionof"essentialaminoacid",indicatetheaminoacidsthatbelongto this group and the sources of these amino acids? In which proteins are all theessentialaminoacidspresent?

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2. Dividetheproteinogeneaminoacidsaccodingtotheirphysico‐chemicalproperties.Fillinthetable.

Hydrophobicaminoacids

Hydrophilicneutralaminoacids

Hydrophilicbasicaminoacids

Hydrophilicacidaminoacids

3.Writethestructureandshowtheroleofthefollowingnon‐proteinogenicaminoacids.

Amino‐acid Structure RoleBeta‐alanine

Homocysteine

Gamma‐aminobutiricacid

DOPA–dioxyphenylalanine

Ornithine

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4.Towhichelectodethefollowingaminoacidswillmovetoainsolutionwithacid,neutralandbasicpH?

Aminoacid pH<7.0 pH=7.0 pH>7.0Alanine Serine Lysine Asparticacid Glutamine

5.WritethereactionofglutamatesidechaincarboxylationinCa2+‐bindingproteins.Whatisthebiologicimportanceofthereaction?

6. Write the reactions of histidine and glutamate decarboxylation. What is the biologicimportanceofthesereactions?

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5. Write the reactions of alanine and aspartic acid transamination with alpha‐ketoglutarate.Whatisthebiologicimportanceofthereaction?

6.Writethefollowingtripeptides:Lys‐Val‐Pro;Glu‐Pro‐Arg;Pro‐Asp‐His.Highlightclassicandatypicpeptidebondsandshowtheirdifferences.

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Testsforselfassessment:1.Whatgroupsofaminoacidsarepresentinproteins?

a) hydroxyaminoacidsb) homocyclicaminoacidsc) beta‐aminoacids

d) diaminodicarboxylicaminoacidse) D‐aminoacids

2.Whatcyclicstructuresarepresentinaminoacidsencounteredintheproteinsandtowhichamino‐acidsidechaintheybelong?

a) purine phenylalanineb) indole triptophanec) imidazole histidined) pyrimidine prolinee) skatole tyrosine

3.Selectthecorrectparis–aminoacid–functionalgroupspecificforthesidechain:

a) arginine guanidinob) alanine thioc) tyrosine phenyld) cysteine hydroxye) triptophane indole

4.Selectnon‐polarhydrophobicaminoacids:

a) Ser b)Val c)Ile d)Trp e)Glu.

5.Selectthebasicaminoacids:a) Ala b)Ser c)Tyr d)Gln e)Lys

6.Selectthecorrectstatementsregardingserine:

a) isahydroxyaminoacidb) itsisoelectricpointisinbasicpHc) isa"non‐essential"aminoacidd) isan"essential"aminoacide) inasolutionwithpH=4migratestotheanode.

7.Selectthecorrectstatementsregardingarginine:

a) atpH=3hasanegativechargeb) itsisoelectricpH(pI)isinalkalinemediac) inhydroxylatedformispresentincollagenstructured) isanaminoacide) hasaguanidinegroupinitsstructure.

8.Whichstatementsarecorrectaboutmethionine?

a) isaderivativeofbutanoicacidb) containsweak‐bondedsulfurc) atpH=7migratestothecathoded) insolutionswithapHlessthanpIitmigratestotheanode;e) isanon‐essentialaminoacid.

9.Whichbondisspecificfortheprimarystructureofproteins?

a) hydrogenb) peptide

c) estherd) ionic

e) disulphide

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LESSON№4 Data_________________

Proteinstructureandfunction.Classificationofproteins.Generalcharacteristicofsimpleandconjugatedproteins

Experiment1.ChromatographycalidentificationoftheaminoacidsMethodsprinciple: Amino acids have different distributive coefficient in water and inorganic solvent (butanol). Amino acid’s velocity of migration is directly proportional totheirsolubilityinbutanol.Procedure:1.Markthetake‐offlineonthechromatographycalpaperwithapencil.2.Pipetteadropofaminoacidsmixtureinthemiddleofthestartingline(thediameterofthespotmustbelessthen5mm),drythespot.3. Introduce the chromatographycal strip in a vessel with the solvents mixture (water‐butanol).Thestripmustbeinverticalpositionandnottouchthevessel.4.Takethestripoutofthevesselwiththesolventsafter90min,markthedistancepassedbythesolvent(useonlypencil)anddrythechromatogram(10minat70‐100ºC).5.Passthestripthrough0,1‐0,2%ninhydrinsolutionanddryitat100ºC.Onthestripwilldevelopseveralcolouredspots.Eachspotcorrespondtooneaminoacid.6.Measurethefollowingdistances:a –fromthetake‐offlinetothemiddleofeachspot;b –fromthetake‐offlinetothesolvent'sfront.

Calculation:thedistributivecoefficientsforeachaminoacidiscalculatedaccordingtothenextformula:Rf=a/b.TheaminoacidsareidentifiedaccordingtothestandardRftable.

StandardRfvalues Drawtheobtainedchromatogramandmarkthetake‐off

line,distances„a”and„b”.

Measurethedistances„a”and„b”.

CalculateRf,Aminoacid

RfAminoacid

Rf

Histidine 0.11 Cysteine 0.40 Glutamine 0.13 Proline 0.43Lysine 0.14 Tyrosine 0.45Arginine 0.20 Asparagine 0.50Asparticacid

0.24 Methionine 0.55

Glycine 0.26 Valine 0.61Serine 0.27 Triptophane 0.66Glutamicacid

0.30 Phenilalanine 0.68

Threonine 0.35 Isoleucine 0.72Alanine 0.38 Leucine 0.73

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Conclusion:Whichaminoacidsarepresentinthesolution?__________________________________________________________________________________________________________________________________________________________________________________________________________________Clinical significance: Thismethod allows to determinewhich amino acids and inwhatamountarepresent indifferentbiologicalsamples.Assaysofdifferentbiologicalsamplesfor amino acid's content and composition are indispensable in clinical diagnosis ofnumeroushereditaryerrorsofmetabolism,liver,kidneysdiseasesetc.

Self‐trainingquestions:

1. Protein levels of structural organization: primary, secondary, tertiary and quaternarystructures,generaldescription.Chemicalbondsthatstabilizeeachstructurallevel.Basicnotionsaboutproteinstructuraldomains.

2. Proteinsclassification.3. Simpleproteins:albuminsandhistones–generalcharacteristic,structuralpeculiarities.Biologicrole.

4. Conjugated (complex) proteins: nucleo‐, phospho‐, lipo‐, glyco‐, chromo‐ andmetalloproteins;theirgeneralcharacteristic.

5. Globularproteins:hemoglobin–structureandbiologicrole.6. Fibrillar proteins: collagen and elastin – peculiarities of amino acids composition andstructure.Biologicrole.

7. Ca2+‐binding proteins: clotting factors, Ca2+‐ATPase, calmodulin and collagen.Peculiaritiesoftheaminoacidcompositionthatensurecalciumfixation.Biomedicalrole.

Casestudy:

1.WhatchangeofthehemoglobinstructureischaracteristicforHbSthatcausessicklecellanemia? What repercussions has this change of the primary structure on the upperstructurallevelsoftheprotein,itsfunctionandstateoftheerythrocytes?

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2. Collagen, calmodulin, plasma coagulation factors II,VII, IX andX, etc. areCa2+‐bindingproteins. What is the common structural property of these proteins? What vitaminensuresthisproperty?Whatarethesourcesofthevitamin?Whataretherolesoftheseproteinsinthebody?

Writethereactioninwhichisinvolvedthisvitamin.

3.Fillinthetable:Thisisthedeffinitionof

Thesequenceofaminoacidsinthepolypep‐tidechain,thatisgeneticallydetermined

Thisisthedeffinitionof Isformedduetotheinteractionofα‐carboxylgroupofoneaminoacidwithα‐aminogroupofthenextaminoacid

What structure has thisproperty?

Coplanarity

What chemical bond hasthisproperty?

resonanceformes(ketoorenol)

Write the structure whichwillilustratethestatement

transpositionofthesubstituentsinrespecttothelinkC‐N

Whatchemicalbondhas thecapacitytoformhydrogenbonds

Example:each peptide group canformtwohydrogenbonds

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4.What are the similarities and differences of hemoglobin andmyoglobin structure andfunction?What type of hypoxia develops in hemoglobin deficiency?What is the normallevelofhemoglobinintheblood?

Testsforself‐assessment:

1.Selectthecorrectstatementsaboutthesecondarystructureoftheproteins:a) isthearrangementintoanorderedstructureofthepolypeptidicchainb) itisdeterminedbyhydrophobicandionicinteractionsc) canbealpha‐helixandbeta‐structured) itisstabilizedbyhydrogenbondinge) itisstabilizedbypeptidebonds

2.Selectthecorrectstatementsaboutthesecondarystructureoftheproteins:

a) occursduetoionicbondingoftheadjacentpolypeptidechainsb) hasminimalandmaximalperiodicityc) canbeboth–alpha‐helixandbeta‐structured) appears due to hydrogen bond formation within a single chain and between

adjacentchainse) itisstabilisedalsobydisulfidebondsthatareformedbetweenMetradicals.

3.Selectthecorrectstatementsaboutthealfa‐helix:

a) predominatesinfibrillarproteinsmoleculesb) possesshelicalsymmetryc) radicalsofaminoacidsareinvolvedintheformationofthebalpha‐helixd) thehydrogenbondsare formedbetween thegroups–C=Oand ‐NHthatbelong tothesamepolypeptidechain

e) thehydrogenbondsare formedbetween thegroups–C=Oand ‐NHthatbelong tothedifferentpolypeptidechain C

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4.Selectthecorrectstatementsaboutthetertiarystructure:a) functionsarebasedonconformationalchangesb) thedomainsarepartofthesestructurec) thedomainsdeterminespecialproteinfunctionsd) itispossibletheinteractionbetweenradicalsAA‐Cys‐Cyse) itispossibletheinteractionbetweenradicalsAA‐Ser‐Ser

5.Selectthepairofaminoacidswhichsidechainscanformhydrogenbonds:

a) Lys Leub) Phe Val

c) Asp Alad) Ser Cys

e) Asn Thr

6.Selectthepairofaminoacidswhichsidechainscanformionicbonds:

a) Lys Glub) Trp Ile

c) Asp Argd) Gln Val

e) His Met

7.Selectthecorrectstatementsaboutthecuaternarystructureofproteins:

a) istheorganizationofsubunitsinasinglefunctionalproteinmoleculeb) is formed due to the non‐covalent bonds between the contact surfaces of thedomains

c) isrigidandstabled) isformedduetocovalentbondinge) isnotdestroyedbydenaturation

8.Selectthecorrectstatementsaboutthecuaternarystructureofproteins:

a) assemblyofthemoleculegoesthroughthestageofintermediatecompoundsb) isfavoredbyhydrophobicinteractionsbetweentheradicalsofaminoacidsc) functioningofproteinsiscorrelatedwiththemovementdomeniiord) isspecificforhemoglobine) isspecificformyoglobin

9.Selecttheoligomers:a) hemoglobin(Hb)b) myoglobinc) LDH(lactatedehydrogenase)d) immunoglobulinse) creatine

10.Selectthecorrectstatementaboutcollagen:

a) thepolypeptidechainshowsclassicalalphahelixconformationb) containsalotofcysteinc) ispresentonlyintracellulard) thestructuralunitofcollagenistropocollagene) tropocollagenunitsareconnectedbyweak,non‐covalentbondsincollagenfibers

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LESSON№5 Data_________________

Physico‐chemicalpropertiesofproteins.Thepurificationandanalysisofproteins

Experiment№1:DialysisMethod's principle: Dialysis (fromGreekδιάλυσις,diàlysis, "dissolution"; from διά,dià,"through",andλύσις,lỳsis,"looseningorsplitting")isamethodofseparationonthebasisofmolecularsize.Smallmoleculescanberemovedfromsolutionsbecausetheypassthroughsemipermeablemembrane.Proteinsarelargerthantheporesofthemembraneanddon'tcrossit.Procedure:1. Mixinaflask20mlsolofovalbumineand20dropsofsaturatedsolutionof(NH4)2SO4.2. Putthesolutioninacellophanebagandimmerseditinaglassfullofdistillatedwater.3. After60minpulloutthebagandtransferthesolutionintoatest‐tube.Identifyproteinand(NH4)2SO4inbothsolutions.

4. Thepresenceofproteinsisdeterminedbybiureticreaction(seeThemenr.1).5. The presence of (NH4)2SO4 is determined with BaCl2. To 5 drops of experimentalsolution add 3‐4 drops of 5% sol. BaCl2. Formation of insoluble BaSO4 certified thepresenceofSO42‐.

BaCl2+(NH4)2SO4BaSO4+2NH4Cl

6. Fillinthetable:

Solution

Compundspresentbefor

dialysis

DIALYSIS

Biureticreaction

ReactionwithBaCl2

Whatcompound–theproteinorSO42‐,ispresentinthesolutionn?

fromthebagProtein

(ovalbumine)(NH4)2SO4

fromtheglass

H2O

Clinicalvalue:Inmedicalpracticedialysisisamethodusedtoremoveexcesswater,othernormalcompundsandwastesfromthebloodofthepatientswhosekidneyshavelosttheirfunctions.Dailysiscanbetemporaryinpersonswithacutekideyfailureorwhoarewaitingfortransplantandchronicifthetransplantisnotindicatedorpossible.Conclusion:_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Self‐trainingquestions:1. Molecularmassoftheproteins.Generalnotionsaboutthemostimportantmethodsfordetermining protein mass – ultracentrifugation, chromatography and massspectroscopy.

2. Amphoteric properties of the protein. The electric charge of the protein. Factors thatdeterminetheelectricchargeoftheprotein.Isoelectricpointandstate.Electrophoresis–principleandbiomedicaluse.Electrophoresisofbloodplasmaproteins.

3. The solubility of the proteins according to the conformation of themolecule and theamino acid composition, solution pH and temperture. Colloidal solutions of proteins.Factorsthatstabilizetheproteincolloidalsolution.Statesofthecolloidalsolutions:sol,gel,xerogel.

4. Denaturation of proteins, agents causing denaturation. Structural changes indenaturatedproteins.Biomedicalrole.

5. Methods of protein separation, purification and analysis: salting, dialysis,electrophoresis and chromatography (ion exchange chromatography, size exclusionchromatography/gelfiltrationchromatographyandaffinitychromatography).Method'sprincipleandbiomedicalimportance.

Casestudy:

1. Writetripeptideswiththeisoelecticpoint(pI)inacidic,neutralandbasicpH.

2. Divide into groups according to their solubility the following proteins: albumin,hemoglobin, keratin, transferrin, IgM, fibrin, prothrombin, collagen. What factorsinfluencethesolubilityoftheseproteins?

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3. Albuminsandhistonesaredissolvedinasolution.Selectbuffersolutionthatshouldbeusedforprecipitationofeachprotein:Sol.1,pH=4.0;Sol.2pH=7.0;Sol.3pH=11.0.Whatisthemechanismofseparationofindividualproteinsfromthemixturebythismethod?

4. Asolutioncontainingamixtureofalbuminsandglobulins is treatedwithammoniumsulfate([NH4]2SO4)tosemisaturation,andthentosaturation.Whateffectwillhavethistreatmentonthesolubilityofalbuminsandglobulins?Whatisthemechanismofactionof[NH4]2SO4ontheproteinsfromthesolution?

5. WhichelectrodealbuminsandhistoneswillmovetoatpH=7,0,ifthestartingpointisin

themiddlebetweenanodeandcathode?Explain.

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6. Whatmethodofthoselistedbelowcanbeusedtopurifyfluids(serum,plasma,lymph)of harmful micro molecular substances: denaturation, hydrolysis, electrophoresis,dialysis,affinitychromatography?Describetheprincipleofthemethodanditsclinicalusefulness.

7. Itisnecessarytoseparateandpurifycertainenzymesfromanimalorplantsourcesfortheproductionofenzymedrugs.Whichofthelistedbelowmethodsisthemostquickand efficient one for the separation and purification of enzymes: denaturation,hydrolysis,electrophoresis,dialysis,affinitychromatography?Describetheprincipleofthemethod.

8. Whatcharacter–hydrophilicorhydrophobic,hasthefragment‐Gly‐Ser‐Asn‐Trp‐Tyr‐

from the primary structure of a protein?Where is located these sequence in the 3Dstructureof theprotein–on thesurficeof themoleculeor inside?Explain.Write thestructureofthesequence.

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Testsforselfassessment:1. SelectthepHrangethatcorrespondtotheisoelectricpointofthepeptide–Arg‐

His‐Lys‐Ala:a) 1,5–3,0 b)3,0–4,5 c)4,5–6,0 d)6,0–7,5e)7,5–9,0

2. Selectthecorrectstatementsabouttheproteinthatcontains10%Arg,26%Lys,13%Val,35%Pro,8%Ala,8%Gly,atphysiologicpH:a) movestotheanodeb) movestothecathodec) hasapositivenetcharge

d) hasanegativenetchargee) doesnothavecharge

3. Selectthecorrectstatementaboutproteinsolubility:a) fibrillarproteinsarewellsolubleinpurewaterb) dependsontheelectricchargeandaqueousmembranec) dependsonthetypeofthesolventanditstemperatured) fibrillarproteinsarebettersolublethenglobularonee) ismaximumattheisoelectricpoint

4.Selectthefactorsthatensurethestabilityoftheproteininthesolution:a) theaqueousmembrane(MA),whichisformedduetothehydrationofthehydrophilicfunctionalgroups

b) theelectriccharge,thatdependsonthepHofthesolutionc) electriccharge,thatdependsonthehydrophobicradicalsofaminoacidsd) theaqueousmembrane(MA),whichis formedduetothehydrationofhydrophobicfunctionalgroups

e) theelectricalchargeofthe"N"‐and"C"‐terminalaminoacids

5.Whatcandeterminetheprecipitationofproteins?a) aqueousmembranedamageb) neutralizationoftheelectricchargec) bringingthebasicproteintotheisoelectricstatebytheadditionofacidd) bringingtheacidproteintotheisoelectricstatebytheadditionofbasee) aqueousmembranedamagebyremovingfixedwater

6.Selectthecorrectstatementsaboutsalting:a) isthehydrationoftheproteinmoleculeb) isthedehydrationoftheproteinmoleculec) isanirreversibleprocessd) isfenomenonofmicromoleculespassingthroughthesemipermeablemembranee) destroysthetertiarystructureoftheprotein

7.Whatstatementsaboutthedenaturedproteinmoleculearecorrect?a) primarystructureisdestroyedb) thebiologicalactivityisincreasedc) tertiaryandquaternarystructuresaredestroyedd) thepeptidebondsaredestoyede) doesnotchangethenativestateofthemoleculeC

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8.Whatpropertiesarespecificforproteincolloidalsolution?a) increasedcapacityofdiffusionb) increasedviscosityc) lowdiffusioncapacity

d) opticalpropertiese) reducedviscosity.

LESSON№ 6 Data_________________

TestonChapterI–Chemistryofproteins

1. Bioelements – organogenic and minerals. Content and overview of the main

bioelementsthatmakeupthehumanbody.Biomolecules.2. Functional groups. Types of functional groups specific for biomolecules. Their

generalfeature.3. Typesofchemicalbondsspecificforbiomolecules.Theirgeneralfeature.4. Water–physicalandchemicalproperties,roleinthelivingorganisms.5. Electrolyticdissociationtheory–basicconcepts.6. ThemainconceptsofBronsted‐Lowryprotolytictheoryofacidsandbases.7. Waterdissociation.Theionicproductofwater.8. ThenotionofpH.Solution’spHandpOHmethodsofdetermination.9. Thebuffersolutions.Principlesofbuffering.Henderson‐Hasselbalchequation.Buffer

capacity.10. BodyliquidspHlevel.Biologicbuffersystems(bicarbonate,phosphate).11. Aminoacids–roleinthelivingorganisms.Aminoacidsproperties–stereoisomery,

solubility,acid‐baseproperties.12. Classificationofaminoacidsaccordingtotheirchemicalstructure,physico‐chemical

andacid‐baseproperties.13. Chemical properties of amino acids – reactions of carboxylation, decarboxylation,

hydroxylationandtransamination.14. Polypeptide theory of the protein structure. Peptide bond properties. Name and

readingtheaminoacidsinpeptidesandproteins.N‐andC‐terminalaminoacids.15. Methods for determination of amino acid composition and sequence in the

polypeptidechain.16. Levels of structural organizationof the proteinmolecule. Theprimary structure of

the protein. Inheritedmodifications of the primary structure ( sickle cell anemia).Proteinsecondarystructure:types,bondsthatstabilizesecondarystructure.

17. Levelsof structural organizationof theproteinmolecule .The tertiary structureoftheprotein.Typesofintramolecularbondsintheprotein.Quaternarystructureoftheprotein. Cooperative changes of protomers conformation (on the example ofhemoglobinandmyoglobin).Term"domain".

18. Globular and fibrillar proteins (hemoglobin, collagen) ‐ peculiarities ofconformationalandphysico‐chemicalproperties.

19. Calcium‐bindingproteins‐collagen,calmodulin,bloodclottingfactors.Peculiaritiesof aminoacid composition resulting calcium fixation .The roleof theseproteins inthebody.

20. The biological role of proteins. Albumin, globulins, histones – their features andbiologicalrole.Methodsfordeterminationandseparationofplasmaproteins.

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21. Classesofconjugatedproteins.General featuresofchromoproteins,metaloproteins,nucleoproteins, phosphoproteins, glycoproteins and lipoproteins, their biologicalrole,examples.

22. Physico‐chemicalpropertiesofproteins.The solubilityof theproteins.Factors thatinfluence solubility. Colloidal solutions of proteins, their properties, stabilizingfactors.Saltingout.Dialysisofproteins.

23. Electro‐chemical properties of proteins. Factors determining the charge of theproteins.Isoelectricstateandpoint.Proteinelectrophoresis.

24. Proteindenaturationandrenaturation.Denaturationfactors.

LESSON№7 Data_________________

Nucleicacids–classification,structureandrole.Nitrogenousbases,nucleosidesandnucleotides–structureandnomenclature

Experiment1:Molisch'sreaction(namedafterAustrianbotanistHansMolisch)Method'sprinciple:isbasedonthedehydrationoftheribosebysulfuricacidtoproduceanaldehyde(furfural),whichcondenseswithtwomoleculesofthymol,resultinginared‐orpurple‐coloredcompound.Procedure:

№ Reagents Testtube1. Yeasthydrolyzate 10drops2. Thymolsol.1% 3drops

Thoroughlyshakethesolution.PourtheH2SO4solutionontothetesttubewall.3. H2SO4concentr. 20‐30drops

Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment2:Molybdenumreaction(phosphoricacididentification)Method'sprinciple:Whenphosphoricacidistreatedwithmolybdenumreagentayellowsedimentisproduced.Procedure:

№ Reagents Testtube1. Yeasthydrolyzate 10drops2. Molybdenumreagent 20drops

Boilthesolution.Coolitinflowingwater

Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________ C

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Self‐trainingquestions:1. Typesofnucleicacids,functionsandcelllocation.2. Chemicalcompositionofnucleicacids:nitrogenousbases,pentosesandphosphate.3. Nucleosidesandnucleotides–structureandfunctions.4. PrimarystructureofDNA.Polynucleotidechain.Phosphodiesterbonds.5. Secondary and tertiary structure of DNA. DNA double helix – Watson‐Crick model

(typesB,AandZ).LevelsofcompactionofDNAmoleculeinprokaryotes(nucleoid)andeukaryotes(nucleosomesandsolenoid).

6. RNAprimary,secondaryandtertiarystructures.PeculiaritiesoftRNA,mRNAandrRNAstructure.

Casestudy:

1.Writetheformulasofthefollowingnucleotides5´‐thymidylacid,5´‐uridylacid,5´‐adenylacidand5´‐deoxyadenylacid.WhichofthesenucleotidesbelongtoDNAandRNA?Showtheglycosidicandestherbonds.

2.WriteinyournotebookthechemicalstructureofthepolynucleotidesequencedT‐dC‐dG‐dA.Which nucleic acid this sequence belongs to?What will be the electric charge of

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given nucleic acid at physiological pH? What is the role of this electrical charge fornucleosomeformation?

3.WriteinyournotebookthechemicalstructureofthepolynucleotidesequenceG‐A‐U‐C.Whichnucleicacidthissequencebelongsto?Showthebondsspecificforthisstructure.IsitpossiblehydrogenbondsformationinRNA?Drawandexplaininwhichcasesthisispossible.

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4. Show the complementary interaction of cytosine with the corresponding nitrogenousbase.

5.ShowthestructureoftheDNAfragmentthatistranscribedifknownthatRNAcontainstheanticodonUGC.

6.WhichisthesequenceoftheanticodoneofthetRNAthatcarrytheaminoacidencoded

by the codoneUCG frommRNA.Whichpyrimidine base is complementar to guanine?Showhowhydrogenbondsbetweenthesenitrogenousbasesareformed.

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7. Represent the structural formula of a DNA fragment that contains two pairs ofcomplementarynitrogenousbases.

8.WritethestructureofATP,ADPandAMP.WhatareATPfunctions?

Testsforself‐assessment:

1.SelectthestructuralelementsofDNA:a) dehydrouracylb) deoxyribose

c) phosphated) thymine

e) ribosylthymine

2.SelecttypesofchemicalbondsthatarepresentinDNA:a)peptidicb)3',5'‐

phosphodiesterc)N‐glycosidic

d)ionicinteractionse)hydrogenbonds

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3.SelectthecorrectstatementsregardingthestructureofDNA:a)isdoublestrandedb)strandsareparallelc)nitrogenousbasesarelocatedinsidethedoublehelixd)strandsarelinkedbetweenthembyphosphodiesterbondse)strandscannotbeseparatedathightemperature

4.SelectcorrectstatementsaboutDNA:a)classic„B”formofDNAcontains10basepairsperturnb)„V”formofDNAcontains11basepairsperturnc)„Z”formcontains12basepairsperturnandisleft‐handedspirald)forallDNAisspecifictheratioG+C/A+T=1e)mainlyislocatedinthecytosol

5.Selectcorrectstatementsaboutnucleosome:a)histoneproteinsareorganizedinoctamers‐doublesetofH4,H3,H2A,H2B;b)octamereiswrappedbydoubleDNAringlengthof146nucleotides;c)arelocatedinmitochondriad)isaformofRNAsupraorganizatione)aremoleculesofextrachromosomalDNA

6.SelectthecorrectstatementsregardingRNA:a)themoleculeismainlydouble‐strandedb)nucleotidecompositioncorrespondtocomplemetatitylawc)theRNAquantityinthecellisconstantd)itisasingle‐strandedpolyribonucleotidee)thespecificnucleotidesareATP,GTP,TTPandCTP

7.SelectthecorrectstatementsregardingmRNA:a)areveryheterogenousmoleculesb)eachgenehasacorrecpondingmRNAmoleculec)aresynthesizedinthecytoplasmd)containsmethylatedguanineatthe5´‐endc)itisconstantlyattachedtotheribosomes

8.SelectthecorrectstatementsregardingtRNA:a)the5´‐endcontainstheCCAtripletb)containsmanyminornitrogenousbasesc)theaminoacidisattachedtothe3´‐endd)contains75‐90nucleotidese)3´‐endcontainstheanticodone

9.SelectthecorrectstatementsregardingtRNA:a)aremoleculeswithsimilarstructureandshapeb)thesecondarystructureofalltRNAhastheshapeofthecloverleafc)allmoleculesarefreeinthecelld)arestructuralelementsoftheribosomese)arecompletelydouble‐strandedmolecules

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LESSON№8 Data_________________

Carbohydrates:classificationandbiologicalrole.Monosacchirides–structure,isomerism,propertiesandbiomedicalimportance

Experiment№1:GlucoseidentificationbyTrommerreaction.Method'sprinciple:WhenglucoseistreatedwithCu(OH)2inalkalinesolution,abrick‐redprecipitateofCu2Oisformed.

CuSO4+2NaOHNa2SO4+Cu(OH)2blue

Glucose+2Cu(OH)2gluconicacid+H2O+2CuOHyellow2CuOHH2O+Cu2Obrick‐red

Procedure: № Reagents Test‐tube1 glucose 2drops2 10%NaOH 6drops3 2%CuSO4 1drop4 H2O 3‐4drops5 Thecolourofthesolution 6 Heatcarefullthemixture7 Thecolourofthesolution

Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment№2:FructoseidentificationbySeliwanoff’stestMethod'sprinciple:Seliwanoff’s testisa testwhichseparatesaldoseandketosesugars.Keto sugars are dehydrated by concentrated acids (HCl) to yield furfurals or theirsubsidiaries which react with resorcinol in Seliwanoff reagent to yield a cherry‐redcomplex.Whenaddedtoaldoses,aslowerformingpinkcolorisseen.

Procedure:

№ ReagentsTest‐tubes

I II1 Resorcinpouder 1‐2grains 1‐2grains2 HClconcentr. 2drops 2drops3 Fructose0.5% 2drops 2drops4 Glucose0.5% 2drops 2drops5 Boilfewminutes6 Thecolourofthesolution C

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Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

Self‐trainingquestions:1. Thebiologicalroleofcarbohydrates.2. Classificationandstructureofthecarbohydrates.3. Structure and properties of the main monosaccharides (glyceraldehyde,dihydroxyacetone,ribose,deoxyribose,glucose,galactose,fructose).

4. Stereoisomerism of monosaccharides: enantiomers, D‐ and L‐ stereoisomers,diastereolsomersandepimers.

5. Linear and cyclic forms of the monosaccharides. Closed ring structure of 5 or morecarbon atoms (pyranose and furanose rings) monosaccharides. Haworthprojections.The role and properties of the hemiacetal hydroxyl, notions of α‐ and β‐anomers.

6. Important chemical reactions ofmonosaccharides (formation of phosphoric esters,N‐andO‐glycosides,oxidationandreduction).

7. Ascorbicacid(vitaminC)structure,synthesisandrole.8. Aminated carbohydrates: glucosamine, galactosamine and sialic acid – structure,formationandbiologicrole.

Casestudy:

1. Which are the similarities and differences between glyceraldehyde anddihydroxyacetone?

Glyceraldehyde DihydroxyacetoneSimilarities

Differences

2. Write the structure of the following compounds and show the difference in theirstructures:

D-glucose L-glucose Type of isomerism

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α‐D‐glucopyranose β‐D‐glucopyranose Type of isomerism

α‐D‐glucopyranose α‐D‐galactopyranose Type of isomerism

3.WritethestructureoftheD‐glucose,D‐galactose,D‐riboseandD‐fructoseanomers.

4.Writethereactionofglucose‐6‐phosphateformationintheorganism.

5.Write thereactionsofD‐glucoseandD‐galactoseoxidation tillgluconicandglucuronicacids.

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6.Ascorbicacid(vitaminC)issynthesizedfromD‐glucoseandistheγ‐lactoneofthe2‐oxo‐L‐gulonicacid.Writetheschemeofvit.CsynthesisfromD‐glucose.Forwhichorganismsisthissyntheticpathwayspecific?Whatisthebiologicroleofthevitamin?

Testsforself‐assessment:1.Functionsofcarbohydratesa)energeticfunctionb)tomaintainoncoticpressurec)areemulsifiers

d)areconstituentsofconnectivetissueandnucleicacidse)transport

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2.Choosecarbohydratesthatarepresentinthehumanbody:a)amyloseb)glucosec)glycogen

d)ribose,deoxyribosee)amylopectin

3.Selectthecorrectstatementsaboutglucose:a)isapolysaccharideb)isaketosec)isanaldohexose

d)has2anomers–alphaandbetae)doesnothaveasymmetriccarbons

4.Selectthecorrectstatementsaboutfructose:a)isanaldopentose

b)isanaldohexosec)isaketopentose

d)isaglucoseisomere)isthemainmonosacchridefromtheblood

5.Selectthemetabolicactiveformofglucose:a)glucosamineb)acetyl‐glucose

c)phosphoricestherd)methylglucose

e)glucosesulfate

6.Whichstatementischaracterizingthemonosaccharides?a)allmonosaccharidescanproduceintramolecularhemiacetalsb)arepolyhydroxycarbonylcompoundsc)areclassifiedinessentialandnon‐essentiald)allmonosaccharideshaveanomerse)canbehydrolysed

7.Choosethecorrectstatementsregardingthestereoisomerismofmonosaccharides:

a)enantiomersdonotpossessopticalpropertiesb)diastereoisomersdifferintheconfigurationofallchiralcarbonatomsc)epimersarediastereoisomerscharacterizedbytheconfigurationofoneasymmetricatomd)D‐mannoseistheepimerofD‐glucoseatthesecondcarbonatome)openformsofmonosaccharidesexistintheformofα‐andβ‐anomers

8. Indicate the process (2) during which these derivatives of carbohydrates areformed(1)‒drawarrows:

a)sorbitol oxidationofglucoseb)glucuronicandiduronicacids reductionofglucoseandfructosec)mannitol reductionofribosed)glucose‐6‐phosphate reductionofmannoseandfructosee)deoxyribose esterificationofglucose

9.Selectthestructuralelementsoftheneuraminicacid:

a)aceticacidb)pyruvicacid

c)galactosamined)glucuronicacid

e)mannosamine

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LESSON№9 Data_________________

Olygoandpolysaccharides–structure,propertiesandbiomedicalimportance

Experiment №1: Demonstration of the reducing properties of carbohydrates(Fehlingreaction)Method'sprinciple:WhenmonosaccharidesaretreatedwithCu(OH)2inalkalinemedium,abrick‐redprecipitateofCu2Oisformed:

CuSO4+2NaOHNa2SO4+Cu(OH)2blueGlucose+2Cu(OH)2gluconicacid+H2O+2CuOHyellow

2CuOHH2O+Cu2Obrick‐redProcedure:

№ ReagentsTest‐tubes

I II III IV V1 4‐5dropsof glucose Fructose succrose starch pathologi‐cal

urine2 Fehlingsolution 4‐5

drops4‐5drops

4‐5drops

4‐5drops

4‐5drops

3 Boilthemixtures4 Thecolourofthe

solution

Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

Self‐trainingquestions:

1. Classification and structure of the olygosaccharides – reducing and non‐reducingdisaccharides(maltose,lactoseandsucrose).Biomedicalrole.

2. Classification,structure,propertiesandbiomedicalroleofthepolysaccharides:a) homopolysaccharides(glycogen,starch,cellulose)b) heteropolysaccharides(hyaluronicacid,chondroitin‐sulfateandheparin).

Casestudy:

1. Sucrosedoesnothavetwoanomerforms.Why?

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2. Whatistheonlydifferenceinthestructureofstarchandcellulose?Howthisdifferencereflectsthepropertiesofthecorrespondingpolysaccharides?

3. Ruminants use cellulose as food, but most mammals can not use it. Explain why.

Writethestructureofthestructuralunitofcellulose.

4.Trehalose–thenon‐reducingdisaccharidethatconsistof2moleculesofα‐D‐glucose,isa

structuralelementofthetoxinproducedbymanymicroorganisms.Writethestructureofthisdisaccharide.

5.Whichheteropolysaccharideconsistsofβ‐D‐glucuronicacidandN‐acetyl‐β‐D‐

glucosaminelinkedbyaβ(1→3)glycosidicbond?Writeitsstructureandexplainitsbiomedicalrole.

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Testsforself‐assessment:1. Selectthestructuralelementofmaltose:a)alpha‐glucoseb)beta‐glucose

c)alpha‐galactosed)beta‐fructose

e)alfa‐ribose

2. Selectthestructuralelementsofsucrose:a)alpha‐glucoseb)beta‐glucose

c)alpha‐galactosed)beta‐fructose

e)alfa‐ribose

3. Selectthestructuralelementsoflactose:a)alpha‐glucoseb)beta‐glucose

c)beta‐galactosed)alfa‐fructose

e)beta‐ribose

4. Selectthecarbohydratesthatcontainalpha‐glucose:a)glycogenb)starch

c)cellulosed)lactose

e)sucrose

5. Selectthecarbohydratesthatcontainbeta‐glucose:a)glycogenb)starch

c)cellulosed)lactose

e)sucrose

6. Selectthecorrectstatementsabouthomoglycans:a)structuralunitofcelluloseismaltoseb)celluloseisapolysaccharidethatpredominatesinplantsc)starchiscomposedofalpha‐glucosed)glycogeniscomposedofbeta‐glucosee)α‐1,6‐glycosidicbondspredominateinthestructureofcellulose.

7.Selectthecorrectstatementsregardingglycogen:a)isdepositedinscheletalmusclesb)isdepositedinadiposetissuec)isdepositedintheliverd)isusedtomaintainthenormallevelofbloodglucosee)itisnotproducedinthehumancells

8.Selectthechemicalbondsthatarespecificforstarch(amylose+amylopectin)andglycogen:

a)α(1→4)b)β(1→4)

c)α(1→6)d)β(1→6)

e)nonofabove

9.Selectthecorrectstatementsaboutheteroglycans:a)mainformsareamylaseandamylopectinb)hyaluronicacidconsistsofD‐glucuronicacidandN‐acetylglucosaminec)inhyaluronicacidthemonomersarelinkedbyβ‐(1→4)andβ‐(1→3)glycosidicbondsd)thereare6formsofchondoritinsulfatee)areimportantstructuralelementsoftheconnectivetissue

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10.Heparin‐selectthecorrectstatementregardingthecompound:a)isamineralcomponentofthebloodplasmab)isaproteinc)isadirectanticoagulantd)isaclottingfactore)isafibrinolyticfactor

LESSON№10 Data_________________

Water‐solublevitamins:B1,B2,B6,PP,biotin,pantothenic,folicandascorbicacidsandB12–structureandcoenzymefunction

Experiment№1:VitaminC(ascorbicacid)levelassayintheurineMethod's principle: Vitamin C has the property of reducing 2,6‐dichlorophenol‐indophenol(2,6‐DCPIP),whichleadstothechangeinthecolorofthesolution.

ascorbicacid+oxidized2,6‐DCPIP→dihydroascorbicacid+reduced2,6‐DCPIP(bluecolor) (pinkcolor)

Procedure:Nr. Reagents Test-tube 1 Urine 10 ml 2 Н2О dist. 10 ml 3 10% НСl sol. 20 drops 4 Initial color of the solution 5 Titrate with 0,001N 2,6-DCPIP solution 6 Final color of the solution

Calculation:TheamountofvitaminCintheurineisdeterminedbytheformula:

C(mg/24ore)=(0.088•A•C)/Bwhere:0,088‐conversionfactor; Aistheamountof2,6‐DCPIPusedtotitratethesample;

B‐theamountofurineusedintheexperiment(10ml);C‐dailydiuresis(onaverage‐1500mlinmenand1200mlinwomen).

Clinical significance:Humans cannot make vitamin C (ascorbic acid or ascorbate) andmustobtainitthroughthefoodorsupplements.VitaminCdisappearsfromtheurineearlyinbloodortissuedepletion.Plasmalevelsfallnextandtissuelevels(suchasinleukocytesandplatelets)arethelasttofall.VitaminClevelsinthebodyof1500mgsorlesswillresultin no urinary excretion of vitamin C. However, certain medications such as aspirin,aminopyrine,barbiturates,hydantoinsandparaldehydeaswellascoldorheatstressareknowntoincreasetheexcretionofvitaminCintheurine.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

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Self‐trainingquestions:1.Classificationandbiomedicalroleofvitamins.2.Water‐solublevitaminsB1,B2,B6,PP,biotin, pantothenic, folic andascorbic acids andB12: a)structure; b)coenzymesderivativesofthesevitamins; c)metabolicfunctionofthecoenzymesderivativesofthesevitamins; d)recommendeddailyallowances(RDAs)andfoodsources;

e)hypo‐andhypervitaminoses–causes,metabolicdisordersandclinicalsigns.

Casestudy:1.Fillinthetableasintheexample:

Vitamin Name Coenzyme BiologicroleHypovitaminosisMainclinicalsigns

B1 Thiamine Thiaminpyrophosphate(TPP)

Coenzymeoftheenzymesthatcatalyzetheoxidativedecarboxylationoftheα‐ketoacids

Beriberi,mentaldepression,mentalconfusion,peripheralneuropathy,ataxia,lossofeyecoordination

B2

B6

PP(B3)

H

B5

B9

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B12

C

Testsforself‐assessment:

1.Selectthefunctionsofthevitamins:a)energeticb)structural

c)transportd)coenzyme

e)genetic

2.Selectthechemicalcompoundsthatcanbecoenzymes:

a)nucleotidesb)proteins

c)hemd)peptides

e)triglycerides

3.Selectthecoenzymesthatcontainadenosinemonophosphates:

a)pyridoxalphosphateb)FMNc)FAD

d)NAD+e)thyaminepyrophosphate

4.Selectthecoenzymesofthedehydrogenases:

a)pyridoxalphosphateb)pyridoxaminephosphatec)thyaminepyrophosphate

d)FADe)NAD+

5.Selectthecoenzymesinvolvedinthetransferoftheaminogroup:

a)folicacidb)FADc)NAD+

d)pantothenicacide)pyridoxalphosphate

6.Selectthecoenzymesinvolvedinthetransferoftheonecarbongroups:

a)folicacidb)FADc)NAD+

d)pantothenicacide)pyridoxalphosphate

7.Selectthereactionsinwhichcanbeinvolvedbiotin:

a)carboxylationb)decarboxylationc)transcarboxylation

d)tranaminatione)dehydrogenation

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8.SelectthecorrectstatemetnsregardingVit.B12:a)containscobaltionb)participateinproteinsynthesisreactionsc)participateintheoxidationoffattyacidswithoddnumberofcarbonsd)participateintheoxidationofvaline,isoleucine,methionine,andthreoninee)ispredominantlypresentinfoodofplantorigin

LESSON№11 Data_________________

ConcludingtestonChapters„NucleicAcidsstructureandfunction”,

„Carbohydratesstructure,propertiesandfunctions”and„Watersolublevitamins”

1. Typesandfunctionsofnucleicacids.2. Structureofnitrogenousbases,nucleosides,nucleotidesandcyclicnucleotides.Chemical

bondsspecificforthenucleotides.Biologicalroleofnucleotides.3. StructureofDNA–doublehelix.Watson‐Crickmodel.TypesB,AandZofdoublehelix.4. Levels of DNA molecule compaction in prokaryotes (nucleoid) and eukaryotes

(nucleosomes,chromatinandchromosomes).5. Generalcharacteristicsandbiologicalroleofcarbohydrates.6. Classificationandfunctionsofcarbohydrates.7. Structureofcarbohydrates:

a)monosaccharides(glyceraldehyde,dihydroxyacetone,ribose,deoxyribose,glucose,galactose,mannose,fructose);b)disaccharides(maltose,lactose,sucrose);c)homopolysaccharides(glycogen,starch,cellulose);d)heteropolysaccharides(hyaluronicacid,chondroitinsulfateandheparin).

9. Stereoisomerism of monosaccharides: enantiomers, D‐ and L‐ stereoisomers,diastereolsomersandepimers.

10. Linear and cyclic formsof themonosaccharides. Closed ring structure of 5 ormorecarbon atoms (pyranose and furanose rings) monosaccharides. Haworthprojections.Theroleandpropertiesofthehemiacetalhydroxyl, notionsofα‐andβ‐anomers.

11. Importantchemicalreactionsofmonosaccharides(formationofphosphoricesters,N‐andO‐glycosides, oxidation and reduction). Ascorbic acid (vitamin C) structure androle.

12. Formationofamino‐carbohydrates(glucosamineandsialicacid),biologicrole.13. Classification of the olygosaccharides – reducing and non‐reducing disaccharides

(maltose,lactoseandsucrose).Biomedicalrole.14. Classification,propertiesandbiomedicalroleofthepolysaccharides:

a) homopolysaccharides(glycogen,starch,cellulose)b) heteropolysaccharides(hyaluronicacid,chondroitin‐sulfateandheparin).

14. Classificationandbiomedicalroleofvitamins.15. Water‐solublevitaminsB1,B2,B6,PP,biotin,pantothenic,folicandascorbicacidsand

B12:a)structure;

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b)coenzymesderivativesofthesevitamins;c)metabolicfunctionofthecoenzymesderivativesofthesevitamins;d)recommendeddailyallowances(RDAs)andfoodsources;e)hypo‐andhypervitaminoses–causes,metabolicdisordersandclinicalsigns.

LESSON№12 Data_________________

Lipids‒classification,structure,physico‐chemicalproperties,biologicalrole.Biologicalmembranes

Experiment№1:FormationofinsolublecalciumsaltsoffattyacidsMethod'sprinciple:Theexperimentisbasedonthefollowingreaction.

2CH3‐(CH2)n‐COOH+CaCl2→(CH3‐(CH2)n‐COO)2Ca+HCl

Procedure:

№ Reagents Test‐tubes

1. Soapsolution 5drops2. CaCl2sol. 1drop

Writethereactionofthecalciumsaltofstearicacidformation.

Rezult:_______________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

Experiment№2:ThesolubilityofcalciumsoapinaceticacidMethod'sprinciple:Theexperimentisbasedonthefollowingreaction.

(CH3‐(CH2)n‐COO)2Ca+CH3COOH→2CH3‐(CH2)n‐COOH+(CH3COO)2Ca

Procedure:

№ Reagents Test‐tubes

1. Usetheprecipitateobtainedinthepreviousesperiment.

2. СН3СООН 2М 1dropRezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

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Self‐trainingquestions:1. Biologicalfunctionsoflipids.2. Classificationoflipids(structural,functional,accordingphysico‐chemicalproperties).3. Saturated and unsaturated fatty acids. Structure, physico‐chemical properties,

representatives.Biomedicalrole.4. Triglycerides‒structure,physico‐chemicalpropertiesandbiomedicalrole.5. Glycerophospholipids: phosphatidylserines, phosphatidylethanolamines (cephalins),

phosphatidylcholines (lecithins), phosphatidylinositols – structure, physico‐chemicalpropertiesandbiomedicalrole.

6. Sphingomyelins‒structure,physico‐chemicalpropertiesandbiomedicalrole.7. Glycolipids: galacto‐ and glucocerebrosides, sulphatides, gangliosides ‒ structure,

physico‐chemicalpropertiesandbiomedicalrole.

Casestudy:1. Vegetable oils are liquid triglycerides and animal fats ‐ solid triglycerides. Write a

triacylglycerolstructurepresentinoilandatriacylglycerolpresentinanimalfat.Givetheirnames.

2. Whatfattyacidsareessentialforthehumanbody?Writetheirstructure.Whatarethe

mainfoodsourcesoftheessentialfattyacids?

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3. What are the products of the basic hydrolysis of phosphatidylcholine that containsstearicandoleicacids?Writethereactionofthehydrolysisprocess.

4. Writethereactionsoftheacidhydrolysisofthefollowingtriglycerides:dioleostearine,linoleodioleineanddipalmitostearine.

5. Writethestructuresofphosphatidylcholinethatcontainspalmiticandoleicacidsand

of phosphatidylehtanolamine that contains linoleic and stearic acids. Show the polarandnon‐polarpartsofthemolecules.

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6. Write the the structures of sphingolipids (ceramide and sphingomyeline) andcerebroside that contain the following fatty acids – palmitic, stearic, oleic andarachidonic.

Testsforself‐assessment:1. Selectthefattyacidsthatareessentialhumans:a)lignoсericb)oleicc)palmitoleic

d)linolenice)linoleic

2. Selectthemonoenicfattyacids(withonedoublebond):a)palmiticb)oleicc)palmitoleic

d)linolenice)linoleic

3. Selectthepolyenicfattyacids(withtwoormoredoublebonds):a)arahidonicb)oleicc)palmitoleic

d)linolenice)linoleic

4. Selectthecorrectstatementsregardingtriglycerides:a)areconstituentsofbiologicalmembranesb)areestersofglycerolandfattyacidsc)representaformofenergystoraged)aresolubleinwatere)arederivativesofphosphatidicacid

5. Selectthecompoundfromwhichthephospholipidsaresynthesized:a)glycerolphosphateb)phosphatidicacidc)phosphoricacid

d)triglyceridese)ceramides

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6. Selectthepolarlipidsfromthefollowing:a)phosphatidylcholineb)phosphatidylserinec)phosphatidylethanolamine

d)phosphatidyinositole)triglycerides

7. Selectthelipidsthatcanproducebilayers:a)triglyceridesb)phosphatidylserinec)phosphatidyl‐ethanolamine

d)phosphatidyinositole)ceramides

8. Selectthecorrectstatementsaboutphosphatidylcholineandphosphatidylethanolamine:a)arerepresentativesofwaxesb)arethemaincomponentsofcellmembranesc)representaformofenergystoraged)arederivativesofphosphatidicacide)havedifferentelectriccharge

9. Selectthecorrectstatementsaboutsphingosine:a)isasaturateddihydroxyaminoalcoolb)isacomponentofsphingomyelinec)isacomponentofglycolipidsd)isaconstituentofglycerophospholipidse)doesn’tenterinthecompositionoftheceramide

10. Selectthecorrectstatementsaboutcerebrosides:a) don’tcontainsphingosineb)containabeta‐galactoseorabeta‐glucoseboundtoceramidec)containoligosaccharidesd)sulfatidesareaclassofsulfatedcerebrosidese)thewhitematterofthebraincontainscerebrosidesinlargeamounts

11.Selectthecorrectstatementsaboutgangliosides:a)containseveralresiduesofglycerolb)containN‐acetylneuraminicacid(NANA)c)containonlyglucoseintheoligosaccharided)containsulfateresidueslinkedtogalactosee)aresituatedontheinnersurfaceofmembranes

LESSON№13 Data__________

Cholesterolanditsderivatives.Steroidhormones.Bileacids

Experiment№1:EmulsificationcapacityofthebyleacidsMethod'sprinciple:Emulsificationistheprocessofmakinganemulsion,allowingfatandwater tomix, by breaking downof large fat globules into smaller, uniformly distributed

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particles.Canbeaccomplishedinthesmallintestinethroughtheactionofbileacids,whichlowertensionatthewatter‐lipidssurfaceduetopolarproperties.Procedure:

Reactive Itest‐tube IItest‐tubeOil 1drop 1dropWater 5drops 5dropsBile ‐ 5drops

Shakethetest‐tubes.Howlonglasttheemulsion

Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment№2:Identificationofbileacids(Pettencofferreaction)Method'sprinciple:WhensucroseistreatedwithconcentratedH2SO4oxymethylfurfurolisformed.Itreactswithbileacidtogenerateared‐violetcomplexcompound.Procedure:Putintoatest‐tube:

Reactive Bile 2dropsSucrose20% 2drops

Shakethetest‐tube.ConcentratedH2SO4 5‐6drops

Wait2‐3minfortheresult.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

Self‐trainingquestions:1. Steran. Cholesterol and cholesterides. Structure, physico‐chemical properties and

biomedicalrole.2. Steroid hormones: glucocorticoids, mineralocorticoids, estrogens, gestagens and

androgens–structureandfunctions.3. Bile acids: cholic, taurocholic and glycocolic acids – structure, properties and

biomedicalrole.

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Casestudy:1. Write the structures of the hydrocarbons from which derive the main classes of

steroids–cholestan,pregnan,androstan,estranandcholan.

2.Writethestructuresanddescribethemainfunctionsofthefollowingsteroidhormones–cortisol,aldosterone,estradiol,progesteroneandtestosterone.

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3. Bile acids are synthesized in the liver cells and conjugatedwith glycine and taurineproducing the the corresponding amides. Write the reactions of glycocholic andtaurocholic acids synthesis. What is the biological significance of bile acidsconjugation?

Testsforself‐assessment:1.Selectthecorrectstatementsregardingcholesterol:

a)istheprecursorofsteroidhormonesb)ishydrophobicc)isastoragelipidd)enterintothecompositionofbiologicalmembranese)istheprecursorofallfat‐solublevitamins

2.Selectthecorrectstatementsaboutthechemicalpropertiesofcholesterol:

a)isanacid b)isasimplelipid

c)isanalcohol d)isanether

e)isanester

3.Choosethecorrectstatementsaboutbileacids: a)contain28carbonatoms b)arenon‐polarcompouns c)aresynthesizedfromcholesterol d)aresynthesizedfromphosphatidicacid e)canemulsifydietaryfats

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4.Indicatebyarrowthecorrectpairs:hormone‐placeofitssynthesis:a)cortisol yellowbodyb)aldosterone ovarianfolliclesc)testosterone cortexoftheadrenalglandsd)estradiol testisLeydigcellse)progesterone

5.Choosethecorrectstatementsaboutcortisol:a)issynthesizedintheliverb)itisaderivativeofpregnanc)isamineralocorticoidd)participatesintheregulationofbloodglucoselevele)contains27carbonatoms

6.Choosetherightstatementsregardingaldosterone:a)itissynthesizedinthecortexoftheadrenalglandsb)itisaderivativeofandrostanec)contains18carbonatomsd)isaglucocorticoide)regulateswaterandelectrolytesmetabolism

7.Regardingprogesterone,thefollowingstatementsaretrue:a)containsanaromaticringb)itissynthesizedintheyellowbodyc)itissynthesizedfromcholesterold)itisusedinmenopausalhormonereplacementtherapye)regulatescarbohydratemetabolism

LESSON№14 Data__________

Fatsolublevitamins–A,D,EandKExperiment№1:IdentificationofvitaminsD(Rosenheimreaction)Method's principle: When vitamins D are treated with concentrated trichloroaceticacid(CCl3COOH)aredcompoundisformed.Thecolorofthecompoundturnsblueintime.Procedure:Putintoatest‐tube:

Reactive VitaminDsol. 5dropsCCl3COOHconc. 5drops

Shakethetest‐tube.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

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Experiment№2:IdentificationofvitaminsAMethod's principle: When vitamins A are treated with concentrated trichloroaceticacid(CCl3COOH)ayellowcompound is formed.The colorof the compound turnsblue intime.Procedure:Putintoatest‐tube:

Reactive VitaminAsol. 5dropsCCl3COOHconc. 10drops

Shakethetest‐tube.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________

Self‐trainingquestions:1. VitaminsD:cholecalciferolandergocalciferol–structure,synthesisandbiologicrole.2. Calcitriol–structure,synthesisandbiologicrole.3. Isoprenoids. Β‐caroten. Fat soluble vitamins:A, E andK – structure and andbiologic

role.

Casestudy:1.SpecifyschematicallythepathwayofcholesterolconversiontovitaminD3(cholecalciferol).WhatisthebiologicalsignificanceofvitaminD?

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2. Writethestructureofβ‐caroteneandshowthefragmentsof isoprenein itsstructure.Whyisβ‐caroteneorange?

3.Whichcompoundsarecalledcarotenoids?Writethestructureofβ‐caroten,retinoland

retinalandshowtheisoprenefragments.WhatarethefunctionsofvitaminA?

4.Writethestructureanddescribetheroleofα‐tocopherol.

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5.WritethstructuresofvitaminK2anditsstructuralanalog–vicasol.Whatfunctionshavethesechemicalcompounds?

Testsforself‐assessment:

1.Selectthecorrectstatementsaboutfatsolublevitamins: a)allcanbesynthesizedinthehumanorganism b)representativesarefolic,pantothenicandascorbicacids c)representativesarevitaminsA,E,DandK d)aredeliveredbythefood e)arestructuralelementsofthemembranes2.SelectthecorrectstatementsaboutvitaminD: a)issynthesizedintheskinformcholesterol b)theactiveformorthevitaminiscalcitriol c)calcitriolisproducedbydehydrogenationintheliverandkidneys d)thevitamincannotbedepositedinthehumanorganism e)oneofitsfunctionsistoregulatecalciumandphosphatemetabolism

3.ChoosetherightstatementaboutthetransformationofvitaminD:a)vitaminDishydroxylatedintheliverandkidneysb)vitaminDishydroxylatedinmusclesandbonesc)theactiveformofvitaminDiscalcitriold)activeformofvitaminDischolecalciferole)calcitriolissynthesizedintheskinbyhydroxylationofcholesterol

4.Calcitriol–selectthecorrectstatements:a)issynthesizedby2reactionsofhydroxylationofvitaminDintheliverandkidneysb)itisaplantformofvitaminDc)regulatesthelevelofglucoseinthebloodd)regulatesthelevelofsodiumandpotassiuminthebloode)hasananticoagulanteffect

5.SelectthecorrectstatementsaboutvitaminA: a)has2forms–β‐carotenandretinol b)has3forms–retinol,retinalandretinoicacid c)β‐carotenisthevitaminprecursor d)regulatesodiumandpotassiumhomeostasis e)isinvolvedinthevisionprocesses

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6.SelectthecorrectstatementsaboutvitaminE: a)hasantioxidantfunction b)isananticoagulant c)regulatesmineralmetabolism d)hasseveralforms,themostactiveisα‐tocopherol e)isanalcohol

7.SelectthecorrectstatementsaboutvitaminK: a)cannotbesynthesizedinthehumanorganism b)isproducedbythebacteriainthelargeintestine c)hasanticoagulantfunction d)participateinthesynthesisofthecalciumbindingproteins e)vicasolistheplantformofthevitamin

LESSON№15 Data__________

Biologicalmembranes.Chemicalcomposition,structural‐functionalorganization,propertiesandfunctions.Membranetransport

Self‐trainingquestions:

1.Biologicalmembranes.a)Thebiologicalandmedicalroleb)Chemicalcomposition‒lipids,proteins,carbohydrates.Theirfunctionalrole.c)Structuralandfunctionalorganization‒fluid‐mosaicmodelofSinger‐Nicolsond)Thepropertiesofmembranes:fluidity,motility,selectivepermeability,asymmetry,self‐assemblingandself‐repairer.e)Structuralandfunctionaldiversityandspecificity.

2.Membranetransport:a)passivetransport:

‐simplediffusion;‐facilitateddiffusion‐glucosetransporters(GLUT),anionexchangers;‐channeltypealphaandbeta(structuralfeatures).

b)activetransport:‐primary(Na+,K+‐ATPase,Ca2+‐ATPase,ABC‐transporters);‐secondary(aminoacidtransporters,glucose).

c)diseasescausedbydeficiencyofmembranechannelsandtransporters.

Casestudy:1.Writethestructuresofmembranelipidsandshowthepolarandnon‐polarparts.

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2.Listthemonosaccharidesfromtheglycocalix.Whichchemicalbondsappearbetweenthesugarsandproteins?

3.Schematicallyrepresent thebiologicalmembrane– lipidbilayer,periferic, integralandtransmembraneproteins,glicocalix.

4. What are the differences between the cytoplasmic membrane of a normal cell and acancercell?

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Testsforselfassessment:1.Selectthechemicalbondsbetweenthemembraneproteinsandlipids:

a)hydrophobicnteractions

b)ionicbonds c)hydrogenbonds

d)peptidebonds e)disulfidebonds

2. Select the correct statementsabout the carbohydrates inbiologicalmembranes(glycocalix):

a)arelocatedonbothsidesofthemembraneb)bindtolipidsandmembraneproteinsnon‐covalentlyonlyc)haveacatalyticfunctiond)determinetheselectivepermeabilityofthemembranese)areresponsiblefortheintercellularinteractionandadhesion

3. Selectthelipidspresentinbiologicalmembranes:

a) triacylglycerolsb) glycerophospholipidsc) cholesterolesters

d) sphingomyelinse) gangliosides

4. Selectthecorrectstatementsabouttheproteinsofbiologicalmembranes:a) arelocatedonlyintheouterlayeroftheplasmamembraneb) canbeperipheral,integralandtransmembranec) havenomobilityd) performtheroleofintercellularinteractione) canbelinkedbycovalentbondswiththecarbohydratesfromthemembranesurface

5. Selectthesubstanceswhichcrosstheplasmamembranebysodiumsimport:

a) proteinsb) aminoacids

c) triglyceridesd) cholesterol

e)glucose

6.Selectthesubstancesthatpassthroughthemembranebysimplediffusion:

a)waterb)aminoacids

c)Ca2+d)cholesterol

e)CO2

7.Selectsubstancesthataretransportedthroughthecellmembranebytranslocases(facilitateddiffusion):

a)K+b)ammonia

c)triglyceridesd)oxygen

e)glucose

8. Select the substances that are transported through themembrane byATP‐ases(primary‐activetransport):

a)proteinsb)nitrogen

c)H+d)glucose

e)Na+

9. Select the substances thatare transported through the cellmembranewith theparticipationofNa+‐dependenttransports(secondaryactivetransport):

a)proteinsb)aminoacids

c)triglyceridesd)cholesterol

e)glucose

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LESSON№16 Data_________________

ConcludingtestonChapters„Lipids”,„Biologicalmembranes”

1. Biologicalfunctionsoflipids.2. Classification of lipids (structural, functional, according physico‐chemical

properties).3. Saturated and unsaturated fatty acids. Structure, physico‐chemical properties,

representatives.Biomedicalrole.4. Triglycerides‒structure,physico‐chemicalpropertiesandbiomedicalrole.5. Glycerophospholipids:phosphatidylserines,phosphatidylethanolamines(cephalins),

phosphatidylcholines(lecithins),phosphatidylinositols–structure,physico‐chemicalpropertiesandbiomedicalrole.

6. Sphingomyelins‒structure,physico‐chemicalpropertiesandbiomedicalrole.7. Glycolipids: galacto‐ and glucocerebrosides, sulphatides, gangliosides ‒ structure,

physico‐chemicalpropertiesandbiomedicalrole.8. Steran. Cholesterol and cholesterides. Structure, physico‐chemical properties and

biomedicalrole.9. Steroid hormones: glucocorticoids, mineralocorticoids, estrogens, gestagens and

androgens–structureandfunctions.10. Bile acids: cholic, taurocholic and glycocolic acids – structure, properties and

biomedicalrole.11. VitaminsD:cholecalciferolandergocalciferol–structureandbiologicrole.Calcitriol

–structureandbiologicrole.12. Isoprenoids.Β‐caroten.Fatsolublevitamins:A,EandK–structureandandbiologic

role.13. Biologicalmembranes.

a)Thebiologicalandmedicalroleb)Chemicalcomposition‒lipids,proteins,carbohydrates.Theirfunctionalrole.c)Structuralandfunctionalorganization‒fluid‐mosaicmodelofSinger‐Nicolsond)Thepropertiesofmembranes:fluidity,motility,selectivepermeability,asymmetry,self‐assemblingandself‐repairer.e)Structuralandfunctionaldiversityandspecificity.

14. Membranetransport:a)passivetransport:

‐simplediffusion;‐facilitateddiffusion‐glucosetransporters(GLUT),anionexchangers;‐channeltypealphaandbeta(structuralfeatures).

b)activetransport:‐primary(Na+,K+‐ATPase,Ca2+‐ATPase,ABC‐transporters);‐secondary(aminoacidtransporters,glucose).

c)diseasescausedbydeficiencyofmembranechannelsandtransporters.