Abstract
Strain 39ET, originally characterized as Clostridium thermohydrosulfuricum strain 39E and later renamed as Thermoanaerobacter ethanolicus strain 39E, shows less than 97 % 16S rRNA gene sequence similarity with the type strain of the type species of the genus Thermoanaerobacter, T. ethanolicus strain JW 200T. On the basis of a polyphasic analysis that included DNA–DNA hybridization studies with the subspecies of Thermoanaerobacter brockii, its closest phylogenetic relatives, strain 39ET represents a novel species of the genus Thermoanaerobacter, for which the name Thermoanaerobacter pseudethanolicus sp. nov. is proposed. The type strain is 39ET (=DSM 2355T=ATCC 33223T).