RESUMEN
The rate of self-purification of oil-contaminated soil increases after introduction of bacteria of the genus Azotobacter. The bacteria can assimilate oil hydrocarbons as the sole source of carbon and energy, both in the presence of fixed nitrogen and during nitrogen fixation. The species Azotobacter chroococcum activates growth of hydrocarbon-oxidizing bacteria present in Devoroil.
Asunto(s)
Azotobacter , Bacterias/metabolismo , Petróleo/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Hidrocarburos/metabolismoRESUMEN
The autoregulation of the phenotypic (populational) variability of the Bacillus cereus strain 504 was studied. The isolated colonial morphotypes of this bacterium were found to differ in their growth characteristics and the synthesis of extracellular proteases. The phenotypic variabilities of vegetative proliferating cells and those germinated from endospores and cystlike refractory cells were different. Bacterial variants also differed in the production of the d1 and d2 factors (the autoinducers of dormancy and autolysis, respectively) and sensitivity to them. The possible role of these factors in the dissociation of microorganisms is discussed.
Asunto(s)
Bacillus cereus/fisiología , Adaptación Fisiológica , Bacillus cereus/crecimiento & desarrollo , Bacillus cereus/metabolismo , Fenotipo , Esporas BacterianasRESUMEN
Comparison of Lentinus edodes with true xylotrophs and humus saprotrophs cultivated under the conditions used in commercial fungal production revealed the following differences in the lipid composition of the fruiting bodies: (1) in L. edodes, fatty acids are characterized by a high C16:0 level and the presence of C16:1; (2) neutral lipids of L. edodes have a high monoglyceride and free fatty acid content and a low triglyceride level; and (3) the main L. edodes phospholipids are phosphatidylethanolamine and cardiolipin. Fruiting bodies of L. edodes differ from its submerged mycelium in lipid quantity and composition. Submerged mycelium contains up to 20% lipids (fruiting bodies contain 3-4%), neutral lipids are predominantly composed of triglycerides and free fatty acids, and the main constituents of phospholipids are phosphatidylcholine and cardiolipin.