Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Gram positive and other bacteria Gram positive bacteria are broken
Document related concepts
Transcript
Gram positive and other bacteria Gram positive bacteria are broken into three groups Firmicutes Mollicutes Actinobacteria Firmicutes-can be nonsporulating or sporulating NonsporulatingStaphylococcus Very common and durable bacterium Resistant to salt, drying, pH, etc. Staphylococcus aureus is human pathogen Streptococcus-make chains of cells Some human pathogens Streptococcus pyogenes Some are part of oral flora Many are associated with dairy (lactococcus) or feces (enterococcus) Sporulating-very durable spores Classified by shape and location of forming spore Generally found in soil Bacillus-very common and durable Some human pathogens B. anthracis-causes anthrax Bt toxin comes from species that produces it to kill larvae Toxin proteins forms crystal that lodges in trachea Clostridium-obligate anaerobes In anaerobic soil conditions Spores can be found in aerobic niches Some human pathogens: tetanus, botulism, gangrene Mollicutes-lack cells walls Mycoplasma-small and very minimal genomes Parasites of plants and animals M. pneumoniae is common human pathogen Actinobacteria-rod shaped or filamentous Gram-positive aerobes Corynebacterium-non-motile rod Form irregular cell arrangements One significant human pathogen-C. diphtheriae Mycobacterium-very waxy cell surface due to mycolic acid Makes cells difficult to stain Many species in soil 2 significant human pathogens M. tuberculosis –TB M. leprae-Hanson’s disease (leprosy) Filamentous Actinobacteria-Streptomyces Produce mycelium that look like fungal growth Dominant in soil and give soil the earthy smell In compost too Obligate aerobes Other bacteria Cyanobacteria-used to be blue-green algae Phototrophic bacteria with complex cell types Gas vesicles for floating Heterocysts are special cells where nitrogen fixation can occur Anoxic inside of cells to increase efficiency Chlamydia-obligate parasite with little biochemical machinery Form smaller reticulate body that infects host cells Expands to full vegetative body, then exits host to repeat cycle Chlamydia trachomatis is very common STD Planctomyces-stalked bacteria with a rudimentary nucleus Aquatic Bacteroides-obligate anaerobe Most common bacterium in human intestine Chlorobium-green sulfur bacteria Uses H2S as electron donor in anoxic conditions Has chlorosomes which are vesicles of bacteriochorophyll Form relationships called consortia with non-phototrophic bacteria Spirochetes-Gram-negative, motile, and coiled Have endoflagellum that facilitates spinning of cell surface and movement In periplasmic space Human pathogens-Treponema pallidum causes syphilis Borrelia burgdorferi causes Lyme disease One of few bacteria with linear chromosomes Deinococcus-incredible resistance to UV radiation, gamma radiation, and drying DNA repair is immense, multiple copies of genes for repair Produce large amounts of carotenoids Aquifex-obligate chemolithotrophic hyperthermophile Most thermophilic of all bacteria (95°C)
