Rhodobium gokarnense sp. nov., a novel phototrophic alphaproteobacterium from a saltern

A pink-pigmented, phototrophic, purple nonsulfur bacterium, strain JA173T, was isolated in pure culture from a saltern in Gokarna, India, in a medium containing 2 % (w/v) NaCl. Strain JA173T was a non-motile Gram-negative rod that multiplied by budding. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JA173T clusters with the class Alphaproteobacteria; highest sequence similarity (98 %) was to the type strain of Rhodobium orientis and 94 % similarity was observed to the 16S rRNA gene sequence of the type strain of Rhodobium marinum. However, DNA–DNA hybridization with R. orientis DSM 11290T revealed a relatedness value of only 35.1 % with strain JA173T. Strain JA173T contained lamellar internal membranes, bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Strain JA173T had an obligate requirement for NaCl (optimum growth at 2–6 %, w/v) and grew photoheterotrophically with a number of organic compounds as carbon source or electron donor. Photoautotrophic, chemoautotrophic and fermentative growth could not be demonstrated. Yeast extract was required for growth. Based on 16S rRNA gene sequence analysis, DNA–DNA hybridization data and morphological and physiological characteristics, strain JA173T is sufficiently different from other species of the genus Rhodobium to be recognized as a representative of a novel species, Rhodobium gokarnense sp. nov. The type strain is JA173T (=ATCC BAA-1215T=DSM 17935T=JCM 13532T)

Thiophaeococcus mangrovi gen. nov., sp. nov., a photosynthetic marine gammaproteobacterium isolated from Bhitarkanika mangrove forest, India

A coccoid, phototrophic purple sulfur bacterium was isolated in pure culture from a mud sample collected from brackish water in the Bhitarkanika mangrove forest of Orissa, India, in a medium containing 2 % NaCl (w/v). This bacterium, strain JA304T, was Gram-negative and had a requirement for NaCl. Intracellular photosynthetic membranes were of the vesicular type. The colour of the phototrophically grown culture was saddle-brown. Bacteriochlorophyll a and the carotenoid lycopene were present as photosynthetic pigments. Strain JA304T was able to grow photolithoautotrophically and could photoassimilate a number of organic substrates. Yeast extract was required for growth of strain JA304T. The DNA G+C content was 68.1–68.9 mol%. 16S rRNA gene sequence comparisons indicate that the isolate represents a member of the Chromatiaceae within the class Gammaproteobacteria. According to sequence comparison data, strain JA304T is positioned distinctly outside the group formed by the four genera Thiocystis, Chromatium, Allochromatium and Thermochromatium, with only 86.7–91.0 % sequence similarity. Distinct morphological, physiological and genotypic differences from these previously described taxa support the classification of this isolate as a representative of a novel species in a new genus, for which the name Thiophaeococcus mangrovi gen. nov., sp. nov. is proposed. The type strain of Thiophaeococcus mangrovi is JA304T (=JCM 14889T =DSM 19863T). PABA, para-aminobenzoic acid The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain JA304T is AM748925. A phase-contrast micrograph and whole-cell absorption spectrum and an acetone spectrum of extracted pigments of strain JA304T are available as supplementary material with the online version of this paper

Marichromatium bheemlicum sp. nov., a non-diazotrophic photosynthetic gammaproteobacterium from a marine aquaculture pond

A rod-shaped, phototrophic, purple sulfur bacterium, strain JA124(T), was isolated in pure culture from a marine aquaculture pond, located near Bhimunipatnam, in a medium that contained 3 % NaCl (w/v). Strain JA124(T) is a Gram-negative, motile rod with a single polar flagellum. Strain JA124(T) has a requirement for NaCl, with optimum growth at 1.5-8.5 %, and tolerates up to 11 % NaCl. Intracellular photosynthetic membranes are of the vesicular type. Bacteriochlorophyll a and probably carotenoids of the spirilloxanthin series are present as photosynthetic pigments. Strain JA124(T) was able to utilize sulfide, sulfate, thiosulfate, sulfite, thioglycollate and cysteine as sulfur sources. Strain JA124(T) was able to grow photolithoautotrophically, photolithoheterotrophically and photo-organoheterotrophically. Chemotrophic and fermentative growth could not be demonstrated. Strain JA124(T) lacks diazotrophic growth and acetylene reduction activity. Pyridoxal phosphate is required for growth. During growth on reduced sulfur sources as electron donors, sulfur is deposited intermediately as a number of small granules within the cell. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that strain JA124(T) clusters with species of the genus Marichromatium belonging to the class Gammaproteobacteria. The highest sequence similarities of strain JA124(T) were found with the type strains of Marichromatium indicum (98 %), Marichromatium purpuratum (95 %) and Marichromatium gracile (93 %). However, DNA-DNA hybridization with Marichromatium indicum DSM 15907(T) revealed relatedness of only 65 % with strain JA124(T). The DNA base composition of strain JA124(T) was 67 mol% G+C (by HPLC). Based on 16S rRNA gene sequence analysis, morphological and physiological characteristics and DNA-DNA hybridization studies, strain JA124(T) (=ATCC BAA-1316(T)=JCM 13911(T)) is sufficiently different from other Marichromatium species to merit its description as the type strain of a novel species, Marichromatium bheemlicum sp. nov

Rhodobacter vinaykumarii sp. nov., a marine phototrophic alphaproteobacterium from tidal waters

A rod-shaped, phototrophic, purple non-sulfur bacterium was isolated in pure culture from seawater collected from the seashore of Visakhapatnam, on the east coast of India, in a medium that contained 2 % NaCl (w/v). Strain JA123(T) was Gram-negative and non-motile and had a requirement for NaCl. Photo-organoheterotrophic and chemo-organoheterotrophic growth occurred with organic compounds as carbon sources and electron donors. Photolithoautotrophic, chemolithoautotrophic and fermentative growth could not be demonstrated. Strain JA123(T) contained vesicular intracellular photosynthetic membrane structures. Bacteriochlorophyll a and probably carotenoids of the spheroidene series were present as photosynthetic pigments. Biotin was required for growth. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that strain JA123(T) clustered with species of the genus Rhodobacter. Based on 16S rRNA gene sequence analysis and morphological and physiological characteristics, strain JA123(T) is sufficiently different from other Rhodobacter species to propose a novel species, Rhodobacter vinaykumarii sp. nov., to accommodate this strain; the type strain is JA123(T) (=DSM 18714(T) =JCM 14544(T) =CCUG 54311(T))

Two novel species of marine phototrophic Gammaproteobacteria: Thiorhodococcus bheemlicus sp. nov. and Thiorhodococcus kakinadensis sp. nov.

Two coccoid phototrophic purple sulfur bacteria were isolated from marine habitats (marine aquaculture pond near Bheemli, Visakhapatnam and marine tidal waters from a fishing harbour, Kakinada) in a medium that contained 3 % NaCl (w/v). Strains JA132T and JA130T are Gram-negative, motile cocci with a single flagellum. Both have an obligate requirement for NaCl. Intracellular photosynthetic membranes are of the vesicular type. Bacteriochlorophyll a and most probably carotenoids of the spirilloxanthin series were present as photosynthetic pigments. Both strains were able to grow photolithoautotrophically and photolithoheterotrophically. Chemotrophic and fermentative growth could not be demonstrated. There is no vitamin requirement for strain JA132T, while strain JA130T requires niacin, biotin and pantothenate as growth factors. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that both strains cluster with species of the genus Thiorhodococcus belonging to the Gammaproteobacteria. The DNA G+C contents of strains JA132T and JA130T were 65.5 and 57.5 mol%, respectively. Based on the 16S rRNA gene sequence analysis, morphological and physiological characteristics, strains JA132T and JA130T are significantly different from each other and from other species of the genus Thiorhodococcus and are recognized as two novel species, for which the names Thiorhodococcus bheemlicus sp. nov. and Thiorhodococcus kakinadensis sp. nov. are proposed. The type strains of T. bheemlicus sp. nov. and T. kakinadensis sp. nov. are JA132T (=MTCC 8120T=ATCC BAA-1362T=JCM 14149T=DSM 18805T) and JA130T (=ATCC BAA-1353T=DSM 18858T=JCM 14150T), respectivel

Rhodovulum marinum sp. nov., a novel phototrophic purple non-sulfur alphaproteobacterium from marine tides of Visakhapatnam, India

A yellowish-brown bacterium was isolated from enrichment cultures inoculated with seawater samples from the eastern coast of India (Visakhapatnam) under photoheterotrophic conditions. Enrichment and isolation in a medium containing 2 % NaCl (w/v) yielded strain JA128T, which has ovoid to rod-shaped cells, also forms chains and is non-motile. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that strain JA128T clusters with the Alphaproteobacteria and the sequence similarity with its closest relatives, Rhodovulum iodosum and Rhodovulum sulfidophilum, was 95 %. Strain JA128T contained vesicular intracytoplasmic membranes, bacteriochlorophyll a and carotenoids of the spheroidene series. Strain JA128T was mesophilic, slightly acidophilic, slightly halophilic and grew photoheterotrophically with a number of organic compounds as carbon source and electron donor. It was unable to grow photoautotrophically, chemoautotrophically or by fermentative modes. It did not utilize sulfide, thiosulfate or hydrogen as electron donors. Thiamine was required as a growth factor. Based on the 16S rRNA gene sequence analysis, morphological and physiological characteristics, strain JA128T was significantly different from other species of the genus Rhodovulum and was recognized as a novel species for which the name Rhodovulum marinum sp. nov. is proposed. The type strain is JA128T (=ATCC BAA 1215T=CCUG 52183T=JCM 13300T)

Rhodovulum visakhapatnamense sp. nov.

A Gram-negative, rod-shaped, phototrophic bacterium (JA181T) was isolated from a tidal water sample. On the basis of 16S rRNA gene sequence similarity, strain JA181T was shown to belong to the class Alphaproteobacteria, most closely related to Rhodovulum sulfidophilum (97.8 % similarity to the type strain), Rhodovulum adriaticum (93 %), Rhodovulum robiginosum (93 %), Rhodovulum iodosum (94 %), Rhodovulum imhoffii (94 %), Rhodovulum strictum (95 %), Rhodovulum euryhalinum (94.6 %) and Rhodovulum marinum (94.6 %). DNA–DNA hybridization with Rdv. sulfidophilum DSM 1374T (relatedness of 39 % with strain JA181T) and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain JA181T from the eight Rhodovulum species with validly published names. Strain JA181T therefore represents a novel species, for which the name Rhodovulum visakhapatnamense sp. nov. is proposed (type strain JA181T =JCM 13531T =ATCC BAA-1274T =DSM 17937T)

Thiohalocapsa marina sp. nov., from an Indian marine aquaculture pond

A spherical-shaped, phototrophic, purple sulfur bacterium was isolated in pure culture from anoxic sediment in a marine aquaculture pond near Bheemli (India). Strain JA142T is Gram-negative and non-motile. It has a requirement for NaCl (optimum of 2 % and maximum of 6 % w/v NaCl). Intracellular photosynthetic membranes are of the vesicular type. In vivo absorption spectra indicate the presence of bacteriochlorophyll a and carotenoids of the okenone series as photosynthetic pigments. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that strain JA142T is related to halophilic purple sulfur bacteria of the genera Thiohalocapsa and Halochromatium, with the highest sequence similarity to Thiohalocapsa halophila DSM 6210T (97.5 %). Morphological and physiological characteristics differentiate strain JA142T from other species of the genera Halochromatium and Thiohalocapsa. Strain JA142T is sufficiently different from Thiohalocapsa halophila based on 16S rRNA gene sequence analysis and morphological and physiological characteristics to allow the proposal of a novel species, Thiohalocapsa marina sp. nov., with the type strain JA142T (=JCM 14780T =DSM 19078T). The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain JA142T is AM491592. A phase-contrast micrograph of cells of strain JA142T, whole-cell and acetone absorption spectra and 16S rRNA gene sequence-based neighbour-joining, maximum-likelihood, minimum-evolution and maximum-parsimony trees are available as supplementary material with the online version of this paper

Rubrivivax benzoatilyticus sp.nov., an aromatic hydrocarbon-degrading purple betaproteobacterium

A brown-coloured bacterium was isolated from photoheterotrophic (benzoate) enrichments of flooded paddy soil from Andhra Pradesh, India. On the basis of 16S rRNA gene sequence analysis, strain JA2(T) was shown to belong to the class Betaproteobacteria, related to Rubrivivax gelatinosus (99 % sequence similarity). Cells of strain JA2(T) are Gram-negative, motile rods with monopolar single flagella. The strain contained bacteriochlorophyll a and most probably the carotenoids spirilloxanthin and sphaeroidene, but did not have internal membrane structures. Intact cells had absorption maxima at 378, 488, 520, 590, 802 and 884 nm. No growth factors were required. Strain JA2(T) grew on benzoate, 2-aminobenzoate (anthranilate), 4-aminobenzoate, 4-hydroxybenzoate, phthalate, phenylalanine, trans-cinnamate, benzamide, salicylate, cyclohexanone, cyclohexanol and cyclohexane-2-carboxylate as carbon sources and/or electron donors. The DNA G+C content was 74.9 mol%. Based on DNA-DNA hybridization studies, 16S rRNA gene sequence analysis and morphological and physiological characteristics, strain JA2(T) is different from representatives of other photosynthetic species of the Betaproteobacteria and was recognised as representing a novel species, for which the name Rubrivivax benzoatilyticus sp. nov. is proposed. The type strain is JA2(T) (=ATCC BAA-35(T)=JCM 13220(T)=MTCC 7087(T))