The family Coriobacteriaceae: reclassification of Eubacterium exiguum (Poco etal. 1996) and Peptostreptococcus heliotrinreducens (Lanigan 1976) as Slackia exigua gen. nov., comb. nov. and Slackia heliotrinireducens gen. nov., comb. nov., and Eubacterium lentum (Prevot 1938) as Eggerthella lenta gen. nov., comb. nov.

Abstract
16S rRNA gene sequences were determined for Eubacterium exiguum and Peptostreptococcus heliotrinreducens. These species were found to be closely related and, together with Eubacterium lentum, to constitute a branch of the Coriobacteriaceae. Two new genera are proposed on the basis of phenotypic characteristics and 16S rRNA gene sequence comparisons: Slackia to include the bile-sensitive species Eubacterium exiguum and P. heliotrinreducens, and Eggerthella to include the bile-resistant Eubacterium lentum. It is proposed that Eubacterium exiguum and Peptostreptococcus heliotrinreducens are transferred to the genus Slackia gen. nov. as Slackia exigua gen. nov., comb. nov. (type strain ATCC 700122T) and Slackia heliotrinireducens gen. nov., comb. nov. (type strain NTCC 11029T). respectively, and Eubacterium lentum is transferred to the genus Eggerthella gen. nov. as Eggerthella lenta gen. nov., comb. nov. with Eggerthella lenta as the type species.