Rhodobacter sediminicola sp. Nov., isolated from a fresh water pond

Abstract

A phototrophic bacterium, designated as strain JA983T, was isolated from a freshwater pond in Gujarat, India. The strain was yellowish brown, catalase-and oxidase-positive, rod-to-oval shaped, Gram-stain-negative and motile. Growth was observed at 20–35 °C. NaCl was not required for optimum growth and up to 5% was tolerated. Growth was observed at pH 6.0–8.0, with an optimum at pH 7.0. An unidentified glycolipid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphos-phatidylglycerol, two unidentified aminolipids (AL1, AL2) and two unidentified lipids (L1 and L2) are the polar lipids of JA983T. Q10 is the only quinone. C18:1 ω7c/C18:1 ω6c is the major fatty acid. JA983T showed highest 16S rRNA gene sequence similarity with the type strains of Rhodobacter sphaeroides (98.99%), Rhodobacter megalophilus (98.99%), Rhodobacter johrii (98.99%) and other members of the genus Rhodobacter with less than 98.7% similarity. In a 16S rRNA gene sequence-based phylogenetic tree, JA983T formed a different sub-clade with its nearest phylogenetic members of genus Rhodobacter. Phenotypic, chemot-axonomic, phylogenetic and genomic [average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) differences indicated that JA983T is significantly different from other species of the genus Rhodobacter and thus represents a novel species of the genus for which the name Rhodobacter sediminicola sp. nov. is proposed. The type strain is JA983T (=KCTC 15782T=NBRC 113843T).