Anaerosphaera aminiphila gen. nov., sp. nov., a glutamate-degrading, Gram-positive anaerobic coccus isolated from a methanogenic reactor treating cattle waste

1 Faculty of Agriculture, Yamagata University, Wakaba-machi 1-23, Tsuruoka, Yamagata 997-8555, Japan 2 Exploratory Research for Advanced Technology (ERATO), JST, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan Correspondence Atsuko Ueki uatsuko{at}tds1.tr.yamagata-u.ac.jp A strictly anaerobic, mesophilic and aminolytic strain (WN036 T ) was isolated from a methanogenic reactor treating waste from cattle farms. Cells were Gram-positive cocci, often occurred in pairs and were non-motile. Although spore formation was not confirmed by microscopic observation of cells, the strain produced thermotolerant cells. The optimum temperature for growth was 35–37 °C and the optimum pH was 6.7. Oxidase, catalase and nitrate-reducing activities were negative. The novel strain did not ferment carbohydrates and grew in PY medium without additional substrates. The strain utilized L -glutamate, L -glutamine, L -histidine and L -arginine as growth substrates. Major fermentation products were acetate and butyrate with a small amount of propionate. The genomic DNA G+C content was 32.5 mol%. The major cellular fatty acids were C 17 : 1 8, C 18 : 1 7 DMA and C 16 : 0 . The diagnostic diamino acid of the cell-wall peptidoglycan was lysine. Glutamic acid, glycine, alanine and aspartic acid were also detected in the cell-wall peptidoglycan. On the basis of 16S rRNA gene sequences, the most closely related species to strain WN036 T were Peptoniphilus asaccharolyticus ATCC 14965 T (89.8 %) and Peptoniphilus indolicus ATCC 29427 T (89.6 %). Based on the differences in the phenotypic and phylogenetic characteristics of strain WN036 T compared with those of closely related species, a novel genus and species, Anaerosphaera aminiphila gen. nov., sp. nov., is proposed. The type strain is WN036 T (=JCM 15094 T =DSM 21120 T ). Abbreviations: CFA, cellular fatty acid; DMA, dimethylacetal; GPAC, Gram-positive, anaerobic cocci; VFA, volatile fatty acid The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain WN036 T is AB298735 .