Lecture 11 Prokaryotes & Viruses (1)-2

8/3/2019 Lecture 11 Prokaryotes & Viruses (1)-2

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Phylogeny of Prokaryotes

Prokaryotes


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Comparison of Three Domains of Life


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Its All in Your Shape

Staphylococcus aureus Listeria monocytogenes

(spirilla)`

Treponema pallidum


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Lyme Disease


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Lyme Disease


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Some Like it Hot

(extremethermophiles)

Old Faithful in Yellowstone National Park


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Some Like it Salty

(extreme halophiles)

The Dead Sea


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and Some like it Smelly(methanogens)

Louisiana Swamp


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Why Are Bacteria Successful?

Rapid cell division (binary fission)

Metabolic diversity(autotrophs &heterotrophs; anaerobes & aerobes )

Formation of resistant cells(endospores)


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Binary Fission


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Metabolic Diversity

Oxidize

(H2S, NH3, Fe 2+ )

(Chemolithotroph)


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Metabolic Relationships to Oxygen

Obligate aerobesuse O2 for cellularrespiration & cannot grow without it.

Facultative anaerobesuse O2 ifpresentbutalso undergo fermentation.

Obligate anaerobespoisoned by O2 andmustundergo fermentation


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Anthrax and Bioterrorism

Gastrointestinal anthrax

Bacillus anthracis

Cutaneous anthrax Inhalation anthrax


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They are Killing Me

Exotoxins: substances secreted bybacteria are toxicHelicobacter pylorireleases ammonia that

kills stomach epithelial cells causing ulcers

Robin Warren & Barry Marshall won Noble Prize in 2005

Endotoxins: components of the outermembranes of certain gram-negativebacteria are toxic.Salmonella typhi causes typhoid fever


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Bacterial Resistance to Antibiotics


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TransformationGriffith Experiment


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GeneralizedTransduction


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Conjugation Transfer of F Plasmid

Sex pilus


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Conjugation with Recombination


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Bacteria having Sex!


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CLASS ACTIVITY

A microbiologist analyzed the DNA of two E. coli

cells, an Hfr cell and an F- cell, before andimmediately after their conjugation. She found that .

A. both cells lost some genes and gained others

B. both cells gained genes but lost none of their originalgenes

C. one cell lost genes and the other gained genes

D.

E

one cell gained genes and the genes of the other wereunchanged

the genes of both cells remained unchanged


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Viruses

ds

ss

ds

ss


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Diversity of Viral Genomes-p.387

Group I

Group II

Group III

Group IV

Group V

Group VI

Herpes simplex I & II

Parvovirus


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Life Cycle of a (Group I) DNA Virus


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Lytic and Lysogenic Cycle-Group I


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Life Cycle of an Enveloped (Group V)

RNA Virus


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Life Cycle of Retroviruses (Group VI)


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HIV: Close-UP


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Emerging Viruses of the 21st

Century on Parade


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Life Cycle of West Nile Virus

encephalitis

(+)ssRNA:Group IV


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2011 Incidence of West Nile Virus in FL


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Ebola Virus

(-)ssRNA:Group V

Hemorrhagic fever


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Severe Acute RespiratorySyndrome (SARS) 2002

(+)ssRNA:Group IV


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(-)ssRNA

Avian Flu Virus H5N1 Pandemic 2007

(-)ssRNA:Group V

Swine Flu Virus H1N1
http://en.wikipedia.org/wiki/Image:Bantam_Rooster.jpg


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Swine Flu Virus-H1N1Pandemic 2009

(-)ssRNA:Group V
http://upload.wikimedia.org/wikipedia/commons/1/19/Swine_influenza_symptoms_on_swine-en.svghttp://upload.wikimedia.org/wikipedia/en/f/f0/H1N1_influenza_virus.jpghttp://upload.wikimedia.org/wikipedia/commons/5/59/Sow_with_piglet.jpg


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Viroids

Circular RNA molecules of several hundred nucleotides
http://www.invasive.org/images/768x512/0656010.jpg

Documents

Lecture 11 Prokaryotes & Viruses (1)-2