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 degrees 31' E 23 degrees 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 degrees C (optimum, 28 degrees 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 isoC(15:0), iso-C-16:0 and iso-C-17:1 omega 9c, and strain DHOAO6(T) had iso-C-17:0 in addition. Their polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminophospholipid, one unidentified phospholipid and two unidentified aminolipids, and strain DHOAO6(T) had phosphatidylmethylethanolamine and one unidentified lipid in addition. The DNA G+C contents of strains DHOAO6(T) and 4 M-K27(T) were 59.1 and 61.7 mol%, respectively. Based on the above results, we propose that strains DHOAO6(T) and 4 M-K27(T) represent two novel species of the genus Dyella, namely Dyelladinghuensis sp. nov. (type strain DHOAO6(T) = KCTC 52129(T) =NBRC 111978(T)) and Dyellachoica sp. nov. (type strain 4 M-K27(T) =GDMCC 1.1189(T) =LMG 30267(T)).