PHENOTYPIC AND GENOTYPIC DIFFERENCES BETWEEN CERTAIN STRAINS OF CLOSTRIDIUM-ACETOBUTYLICUM

It has become evident that several of the strains of Clostridium aceto butylicum that have been employed in physiological studies of the acet one-butanol fermentation, are heterogeneous. Studies of the phenotypic and genotypic characteristics of several of these strains (involving inter alia both pyrolysis mass spectrometry and 16S rRNA sequence dete rminations) demonstrated that the type strain obtained from ATCC was n ot identical with that supplied by NCIMB, and that NCIMB 8052(T) is in fact Clostridium beijerinckii. We therefore suggest that the name Clo stridium acetobutylicum should be restricted to those strains that are genetically closely related to ATCC 824(T) (which include strains DSM 792 and DSM 1731 but not strain P262).