Acidovorax kalamii sp. nov., isolated from a water sample of the river Ganges

Abstract

A Gram-stain-negative, rod-shaped, aerobic, straw yellow, motile strain, designated KNDSW-TSA6^T, belonging to the genus Acidovorax, was isolated from a water sample of the river Ganges, downstream of the city of Kanpur, Uttar Pradesh, India. Cells were aerobic, non-endospore-forming and motile with single polar flagella. It differed from its phylogenetically related strains by phenotypic characteristics such as hydrolysis of urea, gelatin, casein and DNA, and the catalase reaction. The major fatty acids were C16 : 1ω7c/C16 : 1ω6c, C16 : 0 and C18 : 1ω7c/C18 : 1ω6c. Phylogenetic analysis based on 16S rRNA and housekeeping genes (gyrb, recA and rpoB gene sequences), confirmed its placement within the genus Acidovorax as a novel species. Strain KNDSW-TSA6^T showed highest 16S rRNA sequence similarity to Acidovorax soli BL21^T (98.9 %), Acidovorax delafieldii ATCC 17505^T (98.8 %), Acidovorax temperans CCUG 11779^T (98.2 %), Acidovorax caeni R-24608^T (97.9 %) and Acidovorax radicis N35^T (97.6 %). The digital DNA-DNA hybridization and average nucleotide identity values calculated from whole genome sequences between strain KNDSW-TSA6^T and the two most closely related strains A. soli BL21^T and A. delafieldii ATCC 17505^T were below the threshold values of 70 and 95 % respectively. Thus, the data from the polyphasic taxonomic analysis clearly indicates that strain KNDSW-TSA6^T represents a novel species, for which the name Acidovorax kalamii sp. nov. is proposed. The type strain is Acidovorax kalamii (=MTCC 12652^T=KCTC 52819^T=VTCC-B-910010^T).