VirusesViruses-Segments of RNA or DNA -Segments of RNA or DNA contained In a protein coatcontained In a protein coat

Viruses are not living!!!Viruses are not living!!!

1) Viruses are not made of cells1) Viruses are not made of cells

2) Viruses do not grow2) Viruses do not grow

3) Viruses can’t reproduce on their own3) Viruses can’t reproduce on their own

2 Main Shapes of Viruses2 Main Shapes of Viruses

1) Helical Virus1) Helical Virus

- Rodlike- Rodlike

- Capsid proteins - Capsid proteins winding winding around core in a around core in a spiralspiral

2 Main Shapes of Viruses2 Main Shapes of Viruses

2) Polyhedral Virus2) Polyhedral Virus

-Many sides, roughly spherical-Many sides, roughly spherical

-Most efficient at holding viral genes-Most efficient at holding viral genes

BacteriophagesBacteriophages

Viruses that infect Viruses that infect bacteriabacteria

Structure is polyhedron Structure is polyhedron capsid w/ helical tailcapsid w/ helical tail

How can a Virus Reproduce?How can a Virus Reproduce?

Infect a living cellInfect a living cell

Living cell reads viral nucleic acids and Living cell reads viral nucleic acids and produces more virusesproduces more viruses

Bacteriophages go through the lytic or Bacteriophages go through the lytic or lysogenic cyclelysogenic cycle

Lytic CycleLytic Cycle

Viral genes are injected into the host cellViral genes are injected into the host cell

Host cell replicates viral genes and make viral Host cell replicates viral genes and make viral proteins (capsids)proteins (capsids)

Genes and viruses are put togetherGenes and viruses are put together

Process repeats until cell burstsProcess repeats until cell bursts

Lytic CycleLytic Cycle

http://student.ccbcmd.edu/courses/bio141/lecguihttp://student.ccbcmd.edu/courses/bio141/lecguide/unit3/viruses/lytlc.html#rellytde/unit3/viruses/lytlc.html#rellyt

Lysogenic CycleLysogenic Cycle

Viral gene is inserted into host chromosome Viral gene is inserted into host chromosome (provirus)(provirus)

When cell divides, provirus dividesWhen cell divides, provirus divides

Change in environment can begin lytic cycleChange in environment can begin lytic cycle

Lysogenic CycleLysogenic Cycle

http://student.ccbcmd.edu/courses/bio141/http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/viruses/repmatly.htmllecguide/unit3/viruses/repmatly.html

http://www.youtube.com/watch?v=_J9-xKitsd0http://www.youtube.com/watch?v=_J9-xKitsd0

Emerging VirusesEmerging Viruses

Viruses that evolve in Viruses that evolve in geographically geographically isolated areas and isolated areas and are pathogenic to are pathogenic to humanshumans

Hanta VirusHanta Virus

Ebola VirusEbola Virus

Hantavirus Pulmonary SyndromeHantavirus Pulmonary Syndrome

May 1993May 1993

Acute respiratory Acute respiratory symptomssymptoms

Breathing in air Breathing in air contaminated w/ the contaminated w/ the virusvirus

Urine and fecesUrine and feces

Ebola VirusEbola Virus

19761976Severe, often fatal Severe, often fatal diseasediseaseFound in humans and Found in humans and non-human primatesnon-human primatesGabon, Sudan, the Ivory Gabon, Sudan, the Ivory Coast, Uganda, and the Coast, Uganda, and the Republic of the Congo.Republic of the Congo.http://www.cdc.gov/ncidohttp://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispd/dvrd/spb/mnpages/dispages/ebola/ebolatable.htages/ebola/ebolatable.htmm

Why do we encounter emerging Why do we encounter emerging viruses?viruses?

http://ffh.films.com/id/9505/The_Emerging_Virushttp://ffh.films.com/id/9505/The_Emerging_Viruses.htmles.html

PrionsPrions

Proteins and no nucleic acidsProteins and no nucleic acids

Cause disease by influencing how proteins Cause disease by influencing how proteins foldfold

Misfolding spreads like a chain reactionMisfolding spreads like a chain reaction

Mad Cow DiseaseMad Cow Disease

Creutzfeldt-Jakob diseaseCreutzfeldt-Jakob disease

BacteriaBacteria

http://video.google.com/videosearch?http://video.google.com/videosearch?hl=en&q=bacteria&safe=vss&um=1&ie=Uhl=en&q=bacteria&safe=vss&um=1&ie=UTF-8&sa=N&tab=wv#TF-8&sa=N&tab=wv#

What are Bacteria?What are Bacteria?

Single celled, prokaryotic organismsSingle celled, prokaryotic organisms1/10 the size of most eukaryotic cells1/10 the size of most eukaryotic cells

-http://www.cellsalive.com/howbig.htm-http://www.cellsalive.com/howbig.htmHave a single circular piece of DNAHave a single circular piece of DNAReproduce by Binary FissionReproduce by Binary FissionAnaerobic and aerobic processes (Euk are Anaerobic and aerobic processes (Euk are mostly aerobic)mostly aerobic)Flagella is simpleFlagella is simpleSome have piliSome have pili

PiliPilihttp://microbiologybytes.com/video/photosynthesis.htmlhttp://microbiologybytes.com/video/photosynthesis.html

Along with gel-like capsule, pili help bacteria Along with gel-like capsule, pili help bacteria adhere to surfacesadhere to surfaces

Enable Enable ConjugationConjugation-two organisms exchange -two organisms exchange genetic materialgenetic material

Cell WallsCell Walls

Most Bacteria have 2 types of cell wallsMost Bacteria have 2 types of cell walls

-Gram-negative-Gram-negative

-Gram-positive-Gram-positive

The 2 types differ in susceptability to The 2 types differ in susceptability to anti-anti-

bioticsbiotics

-Chemicals that interfere with life-Chemicals that interfere with life

processes in bacteriaprocesses in bacteria

Three Basic ShapesThree Basic Shapes

Bacillus (Bacillus (buh SIHL uhsbuh SIHL uhs))

-Rod shaped-Rod shaped

Coccus (Coccus (KAHK usKAHK us))

-Round shaped-Round shaped

Spirillium (Spirillium (spy RIHL uhmspy RIHL uhm))

-Spiral shaped-Spiral shaped

BaccilusBaccilusNorthwestern Link

CoccusCoccushttp://biology.northwestcollege.edu/biology/b1010lab/bacillus1.jpg

SpirilliumSpirilliumhttp://biology.northwestcollege.edu/biology/b1010lab/bacillus1.jpg

Which is Which???Which is Which???

Aggregating BacteriaAggregating Bacteria

Strepto- form filamentsStrepto- form filaments

Staphylo- form clustersStaphylo- form clusters

How Bacteria Cause HarmHow Bacteria Cause Harm

Metabolize their hostMetabolize their host

Secrete chemical compoundsSecrete chemical compounds

Metabolizing their hostMetabolizing their hostAcneAcne

Propionibacterium acnesPropionibacterium acnes, grow in the oil glands of skin, grow in the oil glands of skin

Metabolize certain kind of oil produced by glandsMetabolize certain kind of oil produced by glands

Oil glands increase oil production during pubertyOil glands increase oil production during puberty

Food increases so bacteria population increasesFood increases so bacteria population increases

http://www.nlm.nih.gov/medlineplus/tutorials/acne/htm/http://www.nlm.nih.gov/medlineplus/tutorials/acne/htm/_no_50_no_0.htm_no_50_no_0.htm

MythsMyths

                              

                                     

Metabolize their HostMetabolize their HostMycobacterium tuberculosisMycobacterium tuberculosis

Once one of most common causes of death (1.6 million in 2005)Once one of most common causes of death (1.6 million in 2005)

Incidence rates have stabalizedIncidence rates have stabalized

Contracted from inhaling droplets of moisture containing bacteriumContracted from inhaling droplets of moisture containing bacterium

Cough up sputum (saliva mixed w/ mucus or puss) and blood, chest Cough up sputum (saliva mixed w/ mucus or puss) and blood, chest pain, fever, fatigue, weight losspain, fever, fatigue, weight loss

Over one third of world population is infected (5-10% will become Over one third of world population is infected (5-10% will become sick)sick)

Secrete Chemical ToxinsSecrete Chemical Toxins

Staphylococcus aureusStaphylococcus aureusCauses most common food poisoningCauses most common food poisoning

Nausea, vomiting, diarrheaNausea, vomiting, diarrhea

Secrete Chemical ToxinsSecrete Chemical Toxins

Clostridium botulinumClostridium botulinumCauses botulismCauses botulism

From improperly heated canned foodFrom improperly heated canned food

Double vision and paralysisDouble vision and paralysis

May die because can’t breathMay die because can’t breath

1g would is potent enough to kill 1 million people1g would is potent enough to kill 1 million people

Relevance of BacteriaRelevance of Bacteria

Living with youLiving with you

FoodFood

AntibioticsAntibiotics

Living with YouLiving with You

Streptococcus pneumoniaeStreptococcus pneumoniae - present in - present in upper respiratory tract of half the upper respiratory tract of half the populationpopulation

E. coliE. coli - Present in small intestine. Aids in - Present in small intestine. Aids in digestiondigestion

Streptococcus aureusStreptococcus aureus - causes most - causes most common staph infections.common staph infections.

Found in Nose and on skinFound in Nose and on skin

FoodFood

Fermented foodFermented food

Pickles, buttermilk, cheese, saurkraut, Pickles, buttermilk, cheese, saurkraut, olives, vinegar, and sourdough breadolives, vinegar, and sourdough bread

AntibioticsAntibiotics

Can be naturally produced by fungus or Can be naturally produced by fungus or imitated chemicallyimitated chemicallyPenicilliumPenicillium was first used antibiotic was first used antibioticEither stop bacteria from multiplying Either stop bacteria from multiplying (bacteriostatic) or interferes with formation (bacteriostatic) or interferes with formation of cell wall or cell contents (bactericidal)of cell wall or cell contents (bactericidal)Over 100 types and most often perscribed Over 100 types and most often perscribed medicinemedicine