Cloacibacillus evryensis gen. nov., sp nov., a novel asaccharolytic, mesophilic, amino-acid-degrading bacterium within the phylum 'Synergistetes', isolated from an anaerobic sludge digester

A novel anaerobic, mesophilic, amino-acid-utilizing bacterium, strain 158, was isolated from an anaerobic digester of a wastewater treatment plant. Cells of strain 158 T were non-motile, rod-shaped (2.0-3.0 x 0.8-1.0 mu m) and stained Gram-negative. Optimal growth occurred at 37 degrees C and pH 7.0 in an anaerobic basal medium containing 1 % Casamino acids. Strain 158(T) fermented arginine, histidine, lysine and serine and showed growth on yeast extract, brain-heart infusion (BHI) medium and tryptone, but not on carbohydrates, organic acids or alcohols. The end products of degradation were: acetate, butyrate, H-2 and CO2 from arginine; acetate, propionate, butyrate, H-2 and CO2 from lysine; and acetate, propionate, butyrate, valerate, H-2 and CO2 from histidine, serine, BHI medium, Casamino acids and tryptone. The DNA G+C content was 55.8 mol%. The 16S rRNA gene sequence of strain 158(T) showed only 92.6% sequence similarity with that of Synergistes jonesii, the only described species of the 'Synergistes' group. The major cellular fatty acids were iso-C-15: 0 (16.63 %), iso-C-15:0 3-OH (12.41 %) and C-17: 1 omega 6c (9.46 %) and the polar fatty acids were diphosphaticlylglycerol, phosphaticlylglycerol, phosphaticlylethanolamine and phosphatidylmonomethylamine; these fatty acid profiles did not resemble those of any recognized bacterial species. Due to the considerable differences in genotypic, phenotypic and phylogenetic characteristics between strain 158(T) and those of its nearest relative, it is proposed that strain 158 T represents a novel species in a new genus, Cloacibacillus evryensis gen. nov., sp. nov., in the phylum 'Synergistetes'. The type strain is 158(T) (=DSM 19522(T)=JCM 14828(T)).