Nine strains capable of metabolizing isoflavones to equol were isolated from human faeces. Four of the strains were characterized by determining phenotypic and biochemical features and their phylogenetic position based on 16S rRNA gene sequence analysis. These strains were related to HKU14 with about 93 % 16S rRNA gene sequence similarity; they were asaccharolytic, obligately anaerobic, non-spore-forming, non-motile and Gram-positive coccobacilli. In enzyme activity tests, arginine dihydrolase, arginine and leucine arylamidases were positive but nitrate reduction, urease and -glucosidase were negative. The major menaquinone was DMMK-6 (dimethylmenaquinone-6), while that of members of the genus was MMK-6 (methylmenaquinone-6). Furthermore, the cell-wall peptidoglycan type of these strains was A1, while that of members of the genus was A4. On the basis of these data, a new genus, gen. nov., is proposed with one species, sp. nov. The type strain of is FJC-B9 (=JCM 14793 =DSM 19450 =CCUG 54925).


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Minimum-evolution (Fig. S1) and maximum-parsimony (Fig. S2) trees showing the positions of the isolated strains among representative members of the family . [PDF](21 KB)


[PDF file of Supplementary Tables S1 and S2](20 KB)

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