Thermovum composti gen. nov., sp nov., an alphaproteobacterium from compost

A Gram-stain-positive thermophilic bacterium, designated strain Nis3(T), was isolated from compost. The strain grew at 23-57 degrees C (optimum, 50 degrees C); no growth was observed below 15 or above 60 degrees C. The pH range for growth was 5.9-8.8 (optimum, 7.0); no growth was observed below pH 5.4 or above pH 9.3. The DNA G + C content of strain Nis3(T) was 63.4 mol%. The dominant quinone type was ubiquinone Q-10. The major fatty acids were C-18:1 omega 7c, C-19:0 omega 8c cyclo and C-18:0. The polar lipids comprised phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylinositol, phosphatidylmonomethylethanolamine, an unknown glycolipid and a ninhydrin-positive phospholipid. 16S rRNA gene sequence analysis assigned this bacterium to the family Phyllobacteriaceae in the Alphaproteobacteria but it shared less than 95.2 % sequence similarity with other members of the family. The chemotaxonomic and phenotypic characteristics of strain Nis3(T) differed in some respects from those of members of the family Phyllobacteriaceae. Therefore, strain Nis3(T) is considered to represent a novel species of a new genus in the family Phyllobacteriaceae, for which the name Thermovum composti gen. nov., sp. nov. is proposed. The type strain is Nis3(T) (=JCM 17863(T)=KCTC 23707(T)).