Rhodoplanes pokkaliisoli sp. nov., a phototrophic alphaproteobacterium isolated from a water logged brackish paddy soil

Abstract

A Gram-negative, rod-shaped, purple non-sulfur bacterial strain, designated JA415T, was isolated from the mud of a pokkali rice field located on Vypeen Island, Ernakulam, Kerala, India. Strain JA415T was motile by means of a single polar flagellum. Photo- and chemo-organoheterotrophic growth was observed using organic compounds as carbon sources and electron donors. Photoand chemolithoautotrophic growth using thiosulfate as electron donor did not occur. Fermentative growth could not be demonstrated. Intracellular photosynthetic membranes were lamellar stacks parallel to the cytoplasmic membrane. Bacteriochlorophyll a and carotenoids of the spirilloxanthin series were present as photosynthetic pigments. Niacin, pantothenate and p-aminobenzoate were required as growth factors. C18:1ω7c was the predominant cellular fatty acid component. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JA415T clustered with members of the genus Rhodoplanes in the class Alphaproteobacteria. On the basis of phenotypic and molecular genetic evidence, it is proposed that strain JA415T be classified as a representative of a novel species of the genus Rhodoplanes, family Hyphomicrobiaceae, with the name Rhodoplanes pokkaliisoli sp. nov. The type strain is JA415T (=KCTC 5711T =NBRC 104972T). © 2009 IUMS.