C Bacteria Archaebacteria Part 2

Bacteria & Archaebacteria Toxins 1. Exotoxins (proteins) o Toxic chemicals released by the bacteria o Caused by gram-positive bacteria 2. Endotoxins o Toxins made of lipids & carbs o Caused by gram-negative bacteria o Released after bacteria dies Gram Staining 1. Gram Positive o Simple cell walls o Large amounts of peptidoglycan o Don’t pick up gram stain and appear purple 2. Gram Negative o Complex cell walls o Small amounts of peptidoglycan o Pick up gram stain and appear pink Antibiotics • Bacteria that affect other bacteria by interfering with cellular functions • Some released by fungi • Kill more than 1 type of organism: broad spectrum antibiotics • Discovered by Flemming Antibiotic resistance • Bacteria mutates regularly and occasionally forms resistant strain • R-plasmids are resistance genes found on separate pieces of DNA called plasmids that are passed to other bacteria in a process called transformation • Can obtain multiple resistance Bacteria in Industry 1. fermenting food (yogurt, cheese) 2. recycling (break down sewage, decompose dead organisms) 3. agriculture (kill insects) 4. bioremediation (clean oil spills)

Cell Parts 1. cell wall o o

some have disease-causing properties some made of peptidoglycans

2. cell membrane o lipid bilayers; embedded proteins 3. DNA o

Attached to cell membrane

4. Plasmid o Self-contained; self-replicating; circular 5. Capsule o Made of polysaccharides (sugar called glycocalyx); Protects form environment 6. Pili o

Short, hairless protein structures that help bacteria connect

7. Endospore o

thick coated structure formed by gram-positive bacteria

8. Movement o

o

Flagella Slime  wavelike movements in outer membrane help move bacteria over slimy secretions

Nutrition Requirements: carbon and energy Heterotroph Get carbon from other organisms

Phototrophic Gets energy from light

Chemotrophic Gets energy from other organisms

Autotroph Get carbon from CO2

Phototrophic Get energy from light

Chemotrophic Get energy from chemicals in surroundings

Respiration 1. Obligate Anaerobe o Cannot live in presence of oxygen 2. Facultative Anaerobe o Can live with or without oxygen 3. Obligate Aerobe o Lives in oxygen Reproduction 1. Asexual o Binary fission 2. Sexual o transformation 

o

bacteria engulfs DNA from environment and adds it to their own DNA

conjugation



o

2 bacteria attach using a pill & transfer using a pili & transfer DNA to each other

transduction 

virus takes DNA from 1 bacteria & inserts it into another

Kingdoms Eubacteria Lack nucleus Lack membrane bound organelles Cell wall has peptidoglycan Unicellular Heterotrophic or autotrophic by chemosynthesis

Archaebacteria Lack nucleus Lack membrane-bound organelles Cell wall lacks peptidoglycan Unicellular Heterotrophic and autotrophic by chemosynthesis

Kingdom Archaebacteria 1. Methanogens o Convert H & CO2  CH4 (methane) o Oxygen is poisonous to them o Environments: deep water, mud, swamps, sewage, cow intestines 2. Halophiles o “salt-loving” o Dead sea/great salt lakes 3. Thermoacidophiles o Live in acidic conditions with extremely high temperatures  Hot springs, volcanic vents o pH > 2; 110°C Kingdom Eubacteria Bacilli: rod shaped Cocci: spherical Spirilla: spiral-shaped Phylum Schizophyta Class Eubacteria o o

Free-living in soil & water Can live symbiotically with other organisms

Class Actinocycota o o o o o

Gram-positive From branching filaments Decompose dead plants & animals Live in soil Create antibiotics that kill neighbouring bacteria to compete for resources

Class Rickettsiae o o o o

Gram-negative Non-motile intracellular parasites Insects carry them & transfer them to animals Cause diseases such as Rocky Mountain Spotted Fever

o

Cause ulcers from a bacteria called holio ctor phylori

Class Spirochaeta o o o

Gram-negative Spiral-shaped Move my flagella

Phylum Cyanophyta • Use photosynthesis for food • Genus Anabaena from specialized cells called heterocysts o Heterocyst: turn atmospheric nitrogen into ammonia for plants • Need light, CO2, nitrogen, water, and minerals to survive • Food source for fresh water organisms • Believed to be first oxygen producing organism • Once called blue algae • can form a “bloom” when there is rapid growth due to extra nitrates and phosphates in the environment Phylum Plochcorophyta • photosynthetic • live symbiotically with marine chordates • use chlorophyll A and B in photosynthesis (same chlorophyll found in plants)