Prokaryotes
Characteristics Nucleoid Region single circular chromosome plasmids mesosome No membranebound organelles Ribosomes (70S) Plasma membrane Cell wall peptidoglycan Capsule glycocalyx Flagella Fimbriae Pili
Asexual Reproduction Binary Fission: DNA replicates and the cell divides in two.
Genetic Recombination
Genetic Recombination Transformation: receives fragments of DNA from the environment
Genetic Recombination Transduction: DNA carried into a cell through viruses
Genetic Recombination Conjugation: exchange of DNA fragments
Classification Shape Gram stain reaction Oxygen requirements Feeding strategies
Shape Coccus: Spherical
Shape Bacillus: Rodshaped
Shape Helical: Spiralshaped
Shape Filamentous
Gram Stain
Gram Stain Bacteria are stained with a violet dye (Crystal violet) and iodine Rinsed in Alcohol Stained again with a red dye (Safranin) Results Violet = gram positive Red = gram negative
Oxygen Requirements Obligate aerobes Obligate anaerobes Facultative anaerobes
Feeding Strategies Based on energy and carbon sources Photoautotrophs Chemoautotrophs Photoheterotrophs Chemoheterotrophs
Feeding Strategies
Nitrogen Metabolism Nitrogen is needed for proteins and nucleic acids Nitrogen fixation - convert atmospheric nitrogen into ammonia Makes nitrogen available for other organisms
Classification
Phylogeny of Prokaryotes
Domain: Bacteria Group: Proteobacteria Salmonella bacillus shape, gram negative, facultative anaerobe Diarrhea, nausea (chicken and reptiles) Endotoxin caused by membrane
Domain: Bacteria Group: Proteobacteria E. coli bacillus shape, gram negative, facultative anaerobe Diarrhea Exotoxin releases proteins that cause illness
Domain: Bacteria Group: Chlamydias Chlamydia coccus shape & gram negative Causes blindness and is the most common STD in the US
Domain: Bacteria Group: Spirochetes Treponema pallidum Syphilis Helical, Gram negative, anaerobic but oxygen tolerant
Domain: Bacteria Group: Spirochetes Borrelia burgdorferi Lyme Disease Helical, Gram negative, low O 2 requirement
Group: Cyanobacteria Contains Chlorophyll A and phycocyanin Filamentous, no stain, facultative anaerobes Only organism on planet that can fix nitrogen and release oxygen pools Domain: Bacteria
Domain: Bacteria Group: Grampositive bacteria Clostridium Bacillus shape (doesn t stain) endospore Obligate anaerobes - exotoxins Causes gangrene, botulism
Domain: Bacteria Group: Grampositive bacteria Bacillus anthracis Bacillus shape (endospore) Aerobic Causes pustules, pneumonia
Domain: Bacteria Group: Gram-positive bacteria Streptococcus Coccus shape & gram positve, anaerobic but are air tolerant Intestinal tract buttermilk, strep throat
Domain: Bacteria Group: Grampositive bacteria Staphylococcus coccus shape & gram positive, facultative anaerobe Most common type of food poisoning, toxic shock syndrome Dangerous in hospitals
Domain: Bacteria: Review Group: Proteobacteria Salmonella E. coli Group: Chlamydias Chlamydia Group: Spirochetes Treponema Borrelia Group: Cyanobacteria Oscillatoria Group: Grampositive bacteria Clostridium Bacillus anthracis Streptococcus Staphylococcus
Domain: Archaea Group: Methanogens methane releasing Group: Halophiles lives in high salt areas Group: Thermophiles lives in extreme temperatures
Symbiotic Relationships Mutualism both benefit Commensalism one benefits, the other is unharmed Parasitism one benefits at the other s expense
Bacteria and Disease Symptoms of disease Exotoxins - secreted by bacteria Endotoxins - components of the cell wall Pathogens Koch s Postulates
Koch s Postulates Isolate microorganism from dead animal Grow microorganism in pure culture Inject microorganism into healthy animal Microorganisms reproduce in animal Microorganisms are isolated again
Bioremediation Sewage Treatment Oil Spills