01:447:390 Lecture Notes - Lecture 12: Horizontal Gene Transfer, Anaerobic Respiration, Phototroph
Document Summary
Diversity of phototrophic bacteria: cyanobacteria: grouping (order level) according to cell morphology (cellular shape, chroococclaes, pleurocapsales, nostocales: specialized cells in which nitrogen is fixed, stigonematales: branching chains, oscillatoriales. Properties of cyanobacteria: ecology: marine (n2 fixation) and freshwater, soils, rocks, in symbiotic relationships (lichens, high morphological and ecological diversity with low functional diversity. Purple nonsulfur and green nonsulfur gets electrons from organic substrates. Purple sulfur bacteria: electrons from the oxidation of h2s, gammaproteobacteria, s0 accumulation either intra- or extracellularly, photosynthetic membranes from vesicles or lamellae, ecology: live in the interface between anoxic and oxic environments that are exposed to light. Ecology and isolation of srb: live in anoxic sulfate rich environments, the major degraders of organic matter in anoxic marine segments. Isolation by incubating samples from anoxic environments anaerobically with sulfate. Dissimilative sulfur-oxidizing bacteria: chemolithotrophs: energy is obtained by oxidation of reduced inorganic compounds: s2-, s0, s2o32, many are autotrophs (also myxotrophs, most are aerobes (also no3-)
