Rhodoplanes piscinae sp. nov. isolated from pond water.

Two strains (JA266(T) 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 C(18 : 1)ω7c (>65 %), with minor amounts of 11-methyl C(18  : 1)ω7c, C(16 : 0), C(16 : 1)ω7c and C(18 : 0) also present. Both strains have the lamellar type of intracellular photosynthetic membranes. Ubiquinone-10 (Q(10)) and rhodoquinone-10 (RQ(10)) 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 JA266(T) 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 JA266(T) and JA333 had gene sequence similarity of 98.7 and 98.9 % with Rhodoplanes serenus TUT3530(T), 96.4 and 96.5 % with Rhodoplanes elegans AS130(T), 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 TUT3530(T). On the basis of phenotypic and genotypic data, it is proposed that strain JA266(T) 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 JA266(T) ( = JCM 14934(T) = KCTC 5627(T)), while strain JA333 ( = NBRC 107574 = KCTC 5962) is an additional strain.

Descriptions of Rhodopseudomonas parapalustris sp. nov., Rhodopseudomonas harwoodiae sp. nov. and Rhodopseudomonas pseudopalustris sp. nov., and emended description of Rhodopseudomonas palustris.

Four strains (JA310(T), JA531(T), JA447 and JA490) of red to reddish brown pigmented, rod-shaped, motile and budding phototrophic bacteria were isolated from soil and freshwater sediment samples from different geographical regions of India. All strains contained bacteriochlorophyll a and carotenoids of the spirilloxanthin series. The major cellular fatty acid of strains JA310(T) and JA531(T) was C(18:1)ω7c, the quinone was Q-10 and polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an aminohopanoid and an unidentified aminolipid. Phylogenetic analysis based on 16S rRNA gene sequences showed that all strains clustered with species of the genus Rhodopseudomonas in the class Alphaproteobacteria. Strains JA531(T), JA447 and JA490 were genotypically (>80% related based on DNA-DNA hybridization) and phenotypically closely related to each other and the three strains were distinct from strain JA310(T) (33% related). Furthermore, all four strains had less than 48% relatedness (DNA-DNA hybridization) with type strains of members of the genus Rhodopseudomonas, i.e. Rhodopseudomonas palustris ATCC 17001(T), Rhodopseudomonas faecalis JCM 11668(T) and Rhodopseudomonas rhenobacensis DSM 12706(T). The genomic DNA G+C contents of strains JA310(T) and JA531(T) were 63.8 and 62.4 mol%, respectively. On the basis of phenotypic, chemotaxonomic and molecular genetic evidence, it is proposed that strains JA310(T) ( = NBRC 106083(T) = KCTC 5839(T)) and JA531(T) ( = NBRC 107575(T) = KCTC 5841(T)) be classified as the type strains of two novel species of the genus Rhodopseudomonas, Rhodopseudomonas parapalustris sp. nov. and Rhodopseudomonas harwoodiae sp. nov., respectively. In addition, we propose that strain DSM 123(T) ( = NBRC 100419(T)) represents a novel species, Rhodopseudomonas pseudopalustris sp. nov., since this strain differs genotypically and phenotypically from R. palustris ATCC 17001(T) and other members of the genus Rhodopseudomonas. An emended description of R. palustris is also provided.

Phaeospirillum tilakii sp. nov., a phototrophic alphaproteobacterium isolated from aquatic sediments.

Two strains (JA492(T) and JA590) of spiral-shaped, anaerobic, Gram-stain-negative, motile, purple non-sulfur bacteria were isolated from aquatic sediments from a bird sanctuary and a stream, respectively, and were characterized by a polyphasic taxonomic approach. Bacteriochlorophyll a and carotenoids (rhodopin, lycopene, hydroxylycopene glucoside and dihydroxylycopene diglucoside) were present as photosynthetic pigments. Intracellular photosynthetic membranes were of the stacked type. The major fatty acids were C(18 : 1)ω7c, C(16 : 0) and summed feature 3 (C(16 : 1)ω6c and/or C(16 : 1)ω7c) in both strains. Ubiquinones and menaquinones were present as major quinone components. The genomic DNA G+C contents of strains JA492(T) and JA590 were 63.8 and 61.5 mol%, respectively. Both strains were closely related (mean DNA-DNA hybridization >70 %). Phylogenetic analysis showed that the strains clustered with species of the genus Phaeospirillum of the family Rhodospirillaceae, class Alphaproteobacteria. Based on 16S rRNA gene sequence analysis, both strains showed highest sequence similarity with Phaeospirillum oryzae JA317(T) (97.2-97.4 %), Phaeospirillum molischianum DSM 120(T) (96.5-96.7 %), Phaeospirillum fulvum DSM 113(T) (96.7-96.9 %) and Phaeospirillum chandramohanii JA145(T) (96.5-96.7 %). DNA-DNA relatedness between strain JA492(T) and its closest relative in the genus Phaeospirillum was less than 42 %. It is evident from phenotypic, chemotaxonomic and molecular genetic data that strain JA492(T) represents a novel species of the genus Phaeospirillum, for which the name Phaeospirillum tilakii sp. nov. is proposed; the type strain is JA492(T) ( = NBRC 107650(T) = KCTC 15012(T)).