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Ch ng 13

Mi lin quan gia cc qu trnhtrao i cht

Trong c thmi qu trnh bin i cc cht khng xy ra ring r m c mi quan hqua li r t cht ch. Mi quan hthhin ctrong qutrnh bin i ca mt nhm cht ln trong mi quan hca qu trnh bini cc nhm cht khc nhau.

Trong cng mt nhm cht mi quan hthhin qua qu trnhngha v d ha. Mi quan ht ng hca s ng ha v d ha thrhinc hai qu trnh xy ra u c cc cht trung gian chung. V d phosphoglyceric aldehyde va l sn phm trung gian trong qu trnh phngii (d ha) va l sn phm trung gian ca qu trnh tng h p (ng ha)saccharose.

Gia cc nhm cht mi quan hdin ra phc t p h n, nhiu hnhthc h n. Tr c ht mi quan h c thhin qua cc cht trung gian.Mt cht l sn phm phn gii ca nhm cht ny li l nguyn liu tng h p cho nhm cht khc. V dAcetyl-CoA l sn phm ca qutrnh phn gii glucoseng th i n l nguyn liu tng h p acid bo.

Mi lin quan t ng hgia cc qu trnh traoi saccharide, lipid, protein, nucleic acid c ngh a quan tr ng trong s sng ca sinh vt. Vd vic chuyn ha tinh bt thnh ng sau to cc cht bo trongnhng thng mang thc vt cng nh ng vt, c ngh a quantr ng trong vic tng khnng chu rt ca chng. Vic chuyn bin cht

bo thnh ng khi ht ny mm s m bo thc n cho phi.Trong qu trnh hat ng sng ca c th, saccharide l cht d tr

quan tr ng; khi c th cn s phn gii thnh phosphoglyceric acid r ithnh pyruvic acid lm nguyn liu cho s tng h p amino acid, acid bov cc cht khc. Cht bo d tr cng c vai tr t ng t, khi phn giicht bo to nn acetyl-CoAt li tng h p amino acid, saccharide Khi trong c thht ngun d tr saccharide v cht bo th protein s b phn gii to ra cc sn phm t c thtng h p lipid, saccharide.

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Qu trnh chuyn ha trn c vai tr quan tr ng c i v i sinh vttd ng ln sinh vt d d ng.

sinh vt t d ng ngun cht hu c s c p do quang h p to ral glucid, tr c ht l glucose. T ngun saccharide, nh s chuynho t ng hm i to ra c cc cht hu c m c th cn n nh lipid, protein, nucleic acid.

sinh vt d d ng sdng nhng cht hu c c sn trong thcn to nn cc cht c tr ng cho c th. Tcc cht protein, lipid ctrong thc n qua qu trnh bin i skin to nn nhng cht c tr ngcho c th. Do thnh phn thc n khng thc y i v i nhu cuca c thcho nn trong qu trnhng ha vic chuyn ha nhm chtny thnh cht hu c khc r t cn thit cho c th.13.1. M i lin quan gi a qu trnh trao i saccharide v traoi lipid

Hai qu trnh traoi lipid v saccharide c mi quan hcht ch v i nhau. Saccharide ddng bin i thnh lipid v ng c li thng quacc cht trung gian l AlPG, PDA v Acetyl-CoA

T glucose qua qu trnh ng phn s to nn pyruvic acid. T

Pyruvic acid b oxy ha sto nn acetyl-CoA. Acetyl-CoA l nguyn liutng h p acid bo.ng th i trong qu trnh ng phn cn to ra AlPG,tAlPG bin i thnh glycero-P , t to nn glycerin. Nhvy t sn phm phn gii ca saccharide to nn nguyn liu c bn tng h plipid l glycerin v acid bo.

Ng c li qua s phn gii lipid s to nn cc cht trung gian lacetyl-CoA, glycerin. T acetyl-CoA, qua chu trnh ornithine s tng h ptr li saccharide. T glycerin to nn glycero-P v t tng h p lisaccharide.

thc vt, vi khun, nm mc, chu trnh glyoxylic l con ng nitr c ti p qu trnh traoi lipid v i qu trnh traoi saccharide. Qua chutrnh ny acid bo sau khi phn gii thnh acetyl-CoA sbin i thnhoxalo acetic acid, t tng h p nn glucose. Ng c li tglucose stoacetyl-CoA v t tng h p tr li lipid.

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Mi lin quan gi a s trao i saccharide v trao i lipid

Saccharide

AlPG

Pyruvic acid

Chu trnh glyoxylic

Acetyl-CoA

Lipid

Acetyl-CoA

Acid bo

Glycero-P

Glycerin

13.2. M i lin quan gi a s trao i saccharide v trao iprotein

Pyruvic acid l mt xch chyu ni lin qu trnh traoi proteinv traoi saccharide.

Glucose qua qu trnh ng phn to ra pyruvic acid. Pyruvicacid l nguyn liu tng h p mt s amino acid trong h alanine:alanine, leucine, valine

Trong qu trnh tng h p protein cn nng l ng ATP, m ATP lsn phm quan tr ng ca qu trnh traoi saccharide.

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S mi lin quan gi a trao i saccharide v trao i protein

Saccharide

13.3. M i lin quan gi a trao i saccharide v trao i nucleic acidTrong qu trnh phn gii saccharide theo con ng

pentosophosphate, Ribozo5-phosphate c to nn. T Riboso-5- phosphate hnh thnh nn phospho-ribosyl-pyrophosphate (PRPP) lnguyn liu tng h p nn cc nucleotide purine v nucleotide pyrimidine.

Ng c li trong qu trnh phn gii nucleic acid Riboso-5P c tothnh. TRiboso 5P shnh thnh cc monosaccharide khc.

Kiu lin quan th2 gia qu trnh traoi nucleic acid v traoisaccharide l s lin quan cht ch gia qu trnh sinh tng h p ccnucleotide diphosphate v nucleotide triphosphate v i mc phn giisaccharide trong tbo v qu trnh phn gii ny gn lin v i qu trnh phosphoryl ho oxy ho. S phn gii saccharide to nng l ng tngh p cc nucleotide diphosphate v nucleotide triphosphate.

Qua qu trnh tng h p saccharide li cn s tham gia ca cc sn phm to ra trong qu trnh traoi nucleic acid, nhUTP tham gia voqu trnh tng h p polysaccharide.

Erylozo4PRibuloso5P APGErytroso4P APEP

Ser Shikimic acid Pyruvic acid

Gly, CysHis Phe, Tyr, Trip Ala, val, leu Asp Glu

Tre, Ila, ArgMet

Arg, ProProtein, L s

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13.4. M i lin quan gi a s trao i protein v trao i lipidTrao i protein v traoi lipid c mi lin quan cht ch thng

qua cc cht trung gian. Sphn gii lipid to nn glycerin v acid bo vmt scht khc nhserine, choline, sphingosine, H3PO4

Tr c ht acid bo b phn gii to ra acetyl-CoA lm nguyn liutng h p nn nhiu loi amino acid. Glycerin trong qu trnh phn giito ra phosphoglyceric acid, t lm nguyn liu tng h p nn nhiuamino acid. Nhng mi quan hny xy ra t ng t nhmi lin quangia saccharide v i protein phn tch trn. Ng c li, khi phn gii protein cng to nn cc h p cht trung gian, t tng h p nn lipid.Cc amino acid do thoi ho protein to ra, b kh amine s to nn ccacid nhpyruvic acid, oxalo acetic acid, -cetoglutaric acid.

Trong s cc acid va nu th pyruvic acid c vai tr quan tr ngtrong qu trnh tng h p lipid. T pyruvic acid, acetyl-CoA c to ra,acetyl-CoA l nguyn liu tng h p nn cc acid bong th i t pyruvic acid cng c th to ra glycerophosphate v t to thnhglycerin. Glycerin v acid bo l nguyn liu tng h p lipid.

Trong qu trnh phn gii lipid sto thnh nn mt l ng l n ATPl ngun nng l ng cho qu trnh traoi protein. Ng c li protein v ichc nng enzyme c vai tr quyt nh i v i cc phn ng xy ra trongtraoi lipid cng nhcc cht khc v khng c enzyme th khng c cc phnng ho sinh xy ra tc l khng c traoi cht.

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Acetyl-CoA

Glycerin Nhng cht khc Acid bo

Glycero-P

AlP

APEP

Pyruvicacid Oxalo aceticacid -Ceto glutaricacid

Fru.1.6d AsPAla, val,leu

Glu

Tre, Met,Ile, Cys Arg,Pro

Rib5P

Ser

Protein

PheHis

Gly, Xyl

Lipid

13.5. M i lin quan gi a trao i protein v trao i nucleic acidGia qu trnh traoi protein v traoi nucleic acid c mi quan

h c bit quan tr ng m biu hin r nht l trong c ch truyn tthng tin di truyn. DNA lm khun sao m thnh RNA

m t tng

h p nn protein. Cu trc phn tprotein c m ho trong DNA.Qu trnh traoi nucleic acid li ph thuc vo s c mt ca cc

phn t protein-enzyme.ng th i mt s amino acid l nguyn liu choqu trnh tng h p nucleic acid nh aspartic acid l nguyn liu tngh p nucleotide pyrimidine, aspartic acid, glutamin, glycine l nguyn liutng h p nucleotide purine.

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V mi quan h m nhiu nh nghin cu cho r ng s tngh p protein l s c p cn s tng h p nucleic acid l qu trnh thc p lmnhim vtham gia vo qu trnh tng h p protein.

Trong qu trnh phn gii protein v i s tham gia ca ATP tonn cc nucleotide-peptid. Cc phn tny lai to nn nhng protein m i lmi m i thnh phn cc protein trong c th. ng th i s tng h p proteincng cn cc nucleotide triphosphat lm ngun nng l ng (ATP, GTP).13.5. M i lin quan gi a trao i lipid v trao i nucleic acid

Gia lipid v nucleic acid c t mi lin quan tr c ti p, chyu llin quan gin ti p qua s traoi saccharide v protein.

Tuy nhin cng c mi lin quan gia hai qu trnh traoi chtny. S .oxi ho acid bo l ngun duy try cho s tng h p ccnucleotide diphosphat v nucleotide triphosphat qua qu trnh phosphorylho. Ngoi ra trong qu trnh tng h p lipid nh tng h p phospholipid cs tham gia ca CTP.

TI LIU THAM KHO

Ti li u ti ng Vi t 1. Tr n Thn (chbin). 1979. Ha sinhi c ng (t p I, II). NxB KH&KT.H Ni.2. Phm Th Trn Chu, Tr n Thng. 2000. Ha sinh hc. Nxb Gio dc. H Ni.3. Nguyn B Lc. 1997. Ha sinh. Nxb Gio dc. H NiTi li u d ch1. Musil J.G., Kurz .K., Novakava .O. 1982Sinh ha hc hin i theo s . Nxb Y hc. H Ni.Ti li u ti ng n c ngoi 1. Farkas G. 1984. Nvnyi anyagcserelettan. Akadmiai Kiad Budapest.2. Lehninger A. L., 2004. Principle of Biochemistry, 4th Edition. W.HFreeman.