24 - Prokaryotes -H

8/7/2019 24 - Prokaryotes -H

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Prokaryotes and Viruses

Diversity of Prokaryotes

Reproduction and Classification

Ecological Roles and Disease

Viruses




A. Prokaryotes

B. Domain Archaea

C. Domain Bacteria

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B. Domain Archaea

(Kingdom Archaebacteria)

1. First found in extremeenvironments (nowfound everywhere)

2. Over 3.5 billion years

old

3. Cell walls usually lackpeptidoglycan

4. Unusual lipid membranes

5. I

ntrons(likeeukaryotes)



6. T here are four major groupsof Archaea

a. Methanogens - producemethane gas (found inbogs, swamps, and

digestive tracts)(CO2 +H2 CH4 +H2O)_





digestive tracts)(CO2 +H2 CH4 +H2O)

b. Hyperthermoacidophiles-live in hot, acidic springs(up to 113OC, pH 2)

c. Extreme Halophiles -tolerate very saltyconditions (use salt togenerate AT P)_





digestive tracts)(CO2 +H2 CH4 +H2O)

b. Hyperthermoacidophiles-live in hot, acidic springs(up to 113OC, pH 2)

c. Extreme Halophiles -tolerate very saltyconditions (use salt togenerate AT P)

d. Psychrophiles ² tolerateextremely coldconditions_



C. Domain Bacteria

(Kingdom Eubacteria)

1. Structures

a. Cell membrane ² similar toeukaryotic lipid bilayer(membrane creates

proton gradient forcellular respiration)

(Photoautotrophs havefolds similar tothylakoids inchloroplasts)

b. Cytoplasm ² containsribosomes and DNA

(Main DNA is single loop. Some have self-replicating plasmids)_

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c. Cell wall composed ofpeptidoglycan

(gram + stain purple)

(gram ² stain light red)

d.Capsule ² polysaccharideslime (Protects against

drying, chemicals, whiteblood cells)

e. Glycocalyx ² capsuleconsists of a sticky,

fuzzy coat of sugars forattachment to hostcells

f. Pili ² hairlike proteinstructures for adheringand transfer of geneticmaterial_



2. Movement

a. flagellum, flagella ortufts of flagella

b. Wave contractions ofouter membrane

c. Spirilla use corkscrewrotations_

3. Endospores

a. dormant, protectivestructure consisting ofthick covering and DNA

b. Gram + only

c. -250OC >100OC

d. Chemical resistant >50

years_



4. Nutrition

a. Saprophytes ² obtain

nutrients from deadorganic matter

b. Photoautotrophs -photosynthesis

c. Chemoautotrophs ²

remove electrons frominorganic molecules

5. Respiration

a. Obligate anaerobes ² O2

poison (clostridium

tetani)b. Facultative anaerobes ²

(Escherichia coli ofdigestive tract)

c. Obligate aerobes ²

(Mycobacteriumtuberculosis)_



6. Shapes and Sizes

a. about 1-10 um

b. bacilli (rod)

c. cocci (sphere)

d. spirilla (spiral)

e. strepto = chain

f. staphylo = cluster

g. diplo = 2_



THE END




A. Reproduction

B. Classification

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A. Reproduction

1. Binary fission- 1 cell dividesinto 2 daughter cells

a. divide every 20 minutes



A. Reproduction


a. divide every 20 minutes_

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2. Genetic recombination:

a. transformation- DNA introduced byenvironment

b. transduction- DNA

introduced by a virusc. conjugation-

donor has specializedplasmid and pilus

pilus attaches to mateand becomesconjugation bridge

Plasmid replicates andone crosses overfollowed by fission_

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1. Bacteria can be divided intoabout 12 major phyla

a. proteobacteria

b. cyanobacteria

c.

spirochetesd. gram + bacteria

e. prochlorophyta_

B. Classification



2. Proteobacteria - Largest,most diverse group (Gram -)

a. Enteric Bacteria

Heterotrophs

A

erobic or anaerobicE.coli (Vitamin K)

Salmonella (Wide use ofantibiotics?)

b. Chemoautotrophs

Extract energy fromminerals (removeelectrons)

c. Nitrogen-Fixing Bacteria

N2 NO3 in root nodules of

legumes (crop rotation)_





4. Spirochetes

a. Gram ²

b. Spiral Shape

c. Corkscrew rotation

d. Aerobic or anaerobice. Free, symbiotic, parastic

f. Syphillis

_



5. Gram + Phylum (Nolipopolysaccharide outermembrane)

a. Not all Gram +

b. Lactobacilli ² tooth decay

via lactic acidc. Streptococci ² strep

throat

d. Actinobacteria ²(Formerly actinomycota)

branching filaments insoil

many produceantibiotics_



6. Prochlorophyta

a. Photosynthetic

b. Live symbiotically withtunicates

c. Genus Prochloron containschlorophyl a and bpigments similar tothose in eukaryotes_



THE END




A. Beneficial Bacteria

B. Pathogenic Bacteria

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1. Decomposers recycle

2. Flavor food

(cheese, sauerkraut, pickles)

3. Convert alcohol to vinegar

4. Break down cellulose5. Leather industry

6. Antibiotics

7. Nitrogen fixers

8. Insulin production9. Bioremediation (sewage, oil,

sulfur)

10. Produce vitamins_




1. Endotoxins

a. Lipids and carbohydratesin certain Gram -membranes

b. Released upon bacterial

death causing fever,body aches, weakness,and blood vessel damage

2. Exotoxins

a. Proteins constantly

released from certainGram + or Gram -bacteria

b. Ex. T etanus_

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3. T issue Destruction

a. Bacteria adhere to cellsand digest membranes

b. Some streptococciproduce blood clot

dissolving enzymes thatcause infection tospread

4. Antibiotics

a. Penicillin ² interferes with

cell wall synthesisb. T etracycline ² interferes

with protein synthesis

c. Broad spectrum

d. Sulfa Drugs_

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5. Bacterial Diseases

a. Bubonic plague

b. Diptheria

c. Botulism

d. T etanuse. T uberculosis

f. Anthrax

g. Pneumonia

h. Whooping Coughi. Syphilis

j. Gonorrhea

k. T yphoid_



6. Prevention

a. Antiseptics

b. Disinfectants

c. Freezing

d. Pasteurizatione. Hygiene_



THE END




A. Characteristics

B. Structure and Function

C. Modes of Nutrition




A. Reproduction

B. Classification



A. Reproduction


a. divide every 20 minutes



2. Genetic transfer:a. transformation- DNA

introduced byenvironment

b. conjugation- DNA

introduced by comingtogether

c. transduction- DNA introduced by a virus



3. Cyanobacteria produce oxygenthrough photosynthesis

a. revolutionized the planet·satmosphere

b. fossilized cyanobacteria

formed stromatolites



4. T here are three major groupsof archaea

a. methanogens producemethane gas

b. hyperthermophiles live in

hot acidic springsc. extreme halophiles

tolerate very saltyconditions_






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24 - Prokaryotes -H