Complete Genome Sequences for the Anaerobic, Extremely Thermophilic Plant Biomass-Degrading Bacteria Caldicellulosiruptor hydrothermalis,

The genus Caldicellulosiruptor contains the most thermophilic, plant biomass-degrading bacteria isolated to date. Previously, genome sequences from three cellulolytic members of this genus were reported (C. saccha-rolyticus, C. bescii, and C. obsidiansis). To further explore the physiological and biochemical basis for polysac-charide degradation within this genus, five additional genomes were sequenced: C. hydrothermalis, C. kristjans-sonii, C. kronotskyensis, C. lactoaceticus, and C. owensensis. Taken together, the seven completed and one draft-phase Caldicellulosiruptor genomes suggest that, while central metabolism is highly conserved, significant differences in glycoside hydrolase inventories and numbers of carbohydrate transporters exist, a finding which likely relates to variability observed in plant biomass degradation capacity. Members of the genus Caldicellulosiruptor are asporogenic, plant biomass-degrading, hydrogen-generating members of th