Rhodoplanes piscinae sp. nov. isolated from pond water

Abstract

Two strains (JA266T and JA333) of Gram-negative, rod-shaped, phototrophic, purple non-sulfur bacteria were isolated from a freshwater fish pond and an industrial effluent. Both strains were capable of phototrophic and chemotrophic growth. Bacteriochlorophyll a and carotenoids of the spirilloxanthin series were present as photosynthetic pigments. The major fatty acid for both strains was C18 : 1ω7c (>65 %), with minor amounts of 11-methyl C18 : 1ω7c, C16 : 0, C16 : 1ω7c and C18 : 0 also present. Both strains have the lamellar type of intracellular photosynthetic membranes. Ubiquinone-10 (Q10) and rhodoquinone-10 (RQ10) were present as primary quinone components. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine were the major polar lipids, while minor amounts of amino lipids (AL1, AL2) and an unidentified lipid (L1) were common to both strains. The DNA G+C contents of strains JA266T and JA333 were 71.3 and 69.9 mol%, respectively. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that both strains clustered with members of the genus Rhodoplanes in the class Alphaproteobacteria . Strains JA266T and JA333 had gene sequence similarity of 98.7 and 98.9 % with Rhodoplanes serenus TUT3530T, 96.4 and 96.5 % with Rhodoplanes elegans AS130T, respectively, and less than 96 % with other members of the genus Rhodoplanes . 16S rRNA gene sequence similarity between the two strains was 99.3 % and they exhibited high (84.7 %) relatedness based on DNA–DNA hybridization. Furthermore, both strains had less than 65 % DNA–DNA relatedness with the type strain R. serenus TUT3530T. On the basis of phenotypic and genotypic data, it is proposed that strain JA266T be classified as a novel species of the genus Rhodoplanes , with the species name Rhodoplanes piscinae sp. nov. The type strain of the proposed novel species is JA266T ( = JCM 14934T = KCTC 5627T), while strain JA333 ( = NBRC 107574 = KCTC 5962) is an additional strain.