Abstract
Six clinical isolates of a hitherto unknown, strictly anaerobic, Gram-negative rod showing fastidious growth were subjected to a polyphasic taxonomic study, including phenotypic, genomic and phylogenetic feature analyses. 16S rRNA gene sequenced-based phylogeny revealed that the novel strains represent a homogeneous group distant from any recognized species in the candidate phylum 'Synergistetes'. The novel isolates were most closely related to species of the genus Dethiosulfovibrio, with 88.2-88.7 % 16S rRNA gene sequence similarity. Large-scale chromosome structure and DNA G+C content also differentiated the novel strains from members of the genus Dethiosulfovibrio. The novel strains were asaccharolytic. Major metabolic end products in trypticase/glucose/yeast extract broth were acetic, lactic, succinic and isovaleric acids and the major cellular fatty acids iso-C(15 : 0) and C(16 : 0). Based on the data presented here, a new genus, Jonquetella gen. nov., is proposed with one novel species, Jonquetella anthropi sp. nov. J. anthropi is the first characterized species of the candidate phylum 'Synergistetes' that includes human isolates. The G+C content of the DNA of the type strain of J. anthropi ADV 126(T) (=AIP 136.05(T)=CIP 109408(T)=CCUG 53819(T)) is 59.4 mol%.