Cohnella baijiui sp. nov., a cellulolytic bacterium isolated from fermented grains of baijiu

A Gram-stain-positive, rod-shaped, motile bacterium, strain REN36^T, was isolated from fermented grains of baijiu. The optimal growth conditions for this organism were observed at a salt concentration of 0% (with a tolerance range of Sodium chloride (NaCl) from 0% to 2%), a temperature of 37 °C (with a tolerance range from 20 to 45 °C) and a pH of 6.0 (with a tolerance range from pH 4.0 to 8.0). The 16S rRNA gene sequence of the isolate showed 98.04% similarity to <i>Cohnella nanjingensis</i> D45^T. The predominant respiratory quinone identified was menaquinone 7, while anteiso-C_15:0 and C_16:0 were the major fatty acids. The polar lipid profile of strain REN36^T included diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, four aminophospholipids, two phospholipids, one glycolipid, one aminoglycolipid, one aminolipid and seven lipids. The DNA G+C content was 58.8 mol%. Notably, strain REN36^T exhibited cellulolytic activity: it utilizes sodium carboxymethyl cellulose as the sole carbon source and encoded three endoglucanases [glycoside hydrolase family 5 (GH5)/GH9] that synergistically degrade cellulose. Digital DNA-DNA hybridization of the isolate with two reference strains showed relatedness values of 29.2% with <i>C. nanjingensis</i> DSM 28246^T and 21.6% with <i>Cohnella ginsengisoli</i> DSM 18997^T. The phylogenetic, chemotaxonomic and phenotypic data supported the classification of strain REN36^T as a representative of a novel species within the genus <i>Cohnella</i>, for which the name <i>Cohnella baijiui</i> sp. nov<i>.</i> is proposed. The type strain is REN36^T (=GDMCC 1.2866^T=JCM 35185^T).