Dyella dinghuensis sp. nov. and Dyella choica sp. nov., isolated from forest soil

Two aerobic, Gram-stain-negative, non-motile, rod-shaped bacterial strains, designated as DHOA06^T and 4 M-K27^T, were isolated from soil samples collected from the forest of Dinghushan Biosphere Reserve, Guangdong Province, PR China (112° 31' E 23° 10' N). Strains DHOA06^T and 4 M-K27^T grew at pH 4.5-7.0 (optimum, pH 5.0-6.0) and pH 4.5-6.5 (pH 6.0), respectively. Both strains grew at 12-37 °C (optimum, 28 °C) and NaCl levels up to 1.0 % (optimum 0 %, w/v). Phylogenetic analysis based on both 16S rRNA gene sequences and the concatenated partial atpD, gyrB andlepA gene sequences showed that strains DHOA06^T and 4 M-K27^T formed two isolated clades with members of the genus Dyella, but they each occupied a distinctive position within the genus. Strains DHOA06^T and 4 M-K27^T showed the highest 16S rRNA gene sequence similarities to Dyellacaseinilytica DHOB09^T (98.7 %) and Dyellaacidisoli 4M-Z03^T (98.8 %), respectively. DNA-DNA hybridization values of strains DHOA06^T/DHOB09^T and 4 M-K27^T/4M-Z03^T were 27.4±2.4 % and 38.8±1.0 %, respectively. Ubiquinone-8 was the only respiratory quinone detected in both strains. Their major fatty acids consisted of iso-C15 : 0, iso-C16 : 0 and iso-C17 : 1ω9c, and strain DHOA06^T had iso-C17 : 0 in addition. Their polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminophospholipid, one unidentified phospholipid and two unidentified aminolipids, and strain DHOA06^T had phosphatidylmethylethanolamine and one unidentified lipid in addition. The DNA G+C contents of strains DHOA06^T and 4 M-K27^T were 59.1 and 61.7 mol%, respectively. Based on the above results, we propose that strains DHOA06^T and 4 M-K27^T represent two novel species of the genus Dyella, namely Dyelladinghuensis sp. nov. (type strain DHOA06^T = KCTC 52129^T=NBRC 111978^T) and Dyellachoica sp. nov. (type strain 4 M-K27^T=GDMCC 1.1189^T=LMG 30267^T).