Thermoanaerobium brockii gen. nov. and sp. nov., a new chemoorganotrophic, caldoactive, anaerobic bacterium

摘要: The isolation of a new anaerobic thermophilic bacterium, Thermoanaerobium brockii, from volcanic features is described. Successful enrichment required complex medium containing glucose or other fermentable sugars and incubation temperatures 55–80° C. Strains T. brockii were gram positive, rods uneven length that existed singly, in pairs, chains filaments. Electron micrographs thin sections cell revealed monolayered wall constrictive “pinching off” division process. organism was nonsporeforming, obligately chemoorganotrophic. optimal temperature for growth 65–70° C, the maxium below 85° C minimum above 35° doubling time at about 1 h. DNA base composition three strains varied 30.0–31.4 mol % guanosine plus cytosine. Fermentable carbohydrates included glucose, sucrose, maltose, lactose, cellobiose insoluble starch. fermentation products cells grown on ethanol, lactic acid, acetic hydrogen carbon dioxide. Growth all tested inhibited by fairly low concentrations cycloserine, penicillin, streptomycin, tetracycline chloramphenicol. possible ecological, evolutionary, industrial significance, taxonomic relationships are discussed.