BIOL 3200 Lecture Notes - Cyanobacteria, Nocardia, Firmicutes
Document Summary
Gram : found in habitats similar to purpl sulfur bacteria, use hydrogen sulfide as source of electrons, many lack flagella but have gas vesicles, sulfur granules that are extracellular, all are strict anaerobes and strictly phototrophic, green in color, other anoxygenic phototrophs, characterized by filamentous growth, metabolically resemble purple non sulfur bacteria, oxygenic phototrohpsgen, photosynthetic bacteria that use water as source of electrons. Inhabit wide range of environments: aqua0c to terrestrial. Able to convert nitrogen gas to ammonia: nitrogen fixa0on. Some organisms single normally prokaryote shapes others form multi-cellular associa0ons called trichomes: nitrogen- fixing cyanobacteria. Important ecologically: can incorporate both nitrogen gas and carbon dioxide into organic material, supports growth of other organisms, helps control atmospheric carbon dioxide. Fixa0on occurs in thick- walled heterocyst: protects the break down of nitrogenase from oxygen, aerobic chemolithotrophs, nitrifers. Motile and often pigmented common opportunistic pathogen: nocardia gram + rod the other acid fast, thermos sp.
