title: Thermophilic anaerobic bacteria which ferment hemicellulose: characterization of organisms and identification of plasmids.
abstract: Seven thermophilic anaerobic bacteria which ferment xylan were isolated from natural geothermal features in the western United States. Typically, these strains were Gram-negative non-sporeforming rods with an unusual double-layered cell wall which resembled that observed in Thermobacteroides acetoethylicus. The strains differed from known thermophilic anaerobes in their ability to utilize a very wide variety of carbohydrates and in their ability to grow in a chemically-defined medium and/or at pH 3.5. Four of the strains contained cryptic plasmids of 1.2 or 1.5 X 10(6) daltons. The taxonomic characteristics of the strains are discussed in terms of their relatedness to those of Thermoanaerobium, Thermoanaerobacter, and Thermobacteroides species.
mesh_terms: D001421:Bacteria, Anaerobic / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D001673:Biodegradation, Environmental; D005285:Fermentation; D006358:Hot Temperature; D010957:Plasmids; D011134:Polysaccharides / Q000378:metabolism*
chemical_list: D011134:Polysaccharides; C007916:hemicellulose