Sphingomonas changnyeongensis sp. nov. isolated from the Hapcheon-Changnyeong barrage area in the Nakdong river

Abstract

The novel bacterial strain C33(T) was isolated from a freshwater sample collected from the Hapcheon-Changnyeong barrage. The Gram-negative, motile, yellow-pigmented strain C33(T) was characterized as a rod-shaped and strictly aerobic bacterium. A 16S-rRNA phylogenetic analysis revealed that this strain was most closely related to Sphingomonas changbaiensis V2M44(T), Sphingomonas tabacisoli X1-8(T), and Sphingomonas flavalba ZLT-5(T) with 97.1, 97.0, and 95.0 % 16S-rRNA sequence similarities, respectively. The genomic DNA GC content of strain C33(T) was estimated at 65.0 mol%. The average nucleotide identity of strain C33(T) relative to S. changbaiensis V2M44(T) and S. flavalba ZLT-5(T) was found to be 77.0 and 75.6%, with average amino-acid identities of 69.9, and 66.7%, and the digital DNA-DNA hybridization values of 21.3 and 17.7%, respectively. The cells grew at 19-37 degrees C and pH 6-9 with 0-0.5% (w/v) NaCl (optimum: 28 degrees C, pH 6.5, and 0% NaCl). The major component identified in the polyamine pattern was sym-homospermidine, and the main ubiquinone was Q-10. The predominant polar lipids characterized were diphophatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, and sphingoglycolipid. Iso-C-15:0, C-15:0 anteiso, and summed feature 3 (C-16:1 omega 6c and/or C-16:1 omega 7c) were found to be the primary cellular fatty acids in strain C33(T). Based on these genotypic and phenotypic characteristics, strain C33(T) was classified as a novel species of the genus Sphingomonas; and the name Sphingomonas changnyeongensis sp. nov. is proposed (=KACC 21511(T)=JCM 33880(T)).