Rhodovulum algae sp. nov., isolated from an algal mat.

A reddish-brown-pigmented, phototrophic bacterium, designated strain JA877T, was isolated from a brown algae mat sample collected from Jalandhar beach, Gujarat, India. On the basis of the 16S rRNA gene sequence, strain JA877T belongs to the class Alphaproteobacteria and is closely related to the type strains Rhodovulum viride JA756T (99.0 %), Rhodovulum sulfidophilum Hansen W4T (98.9 %), Rhodovulumvisakhapatnamense JA181T (98.8 %),Rhodovulum kholense JA297T (97.5 %) and Rhodovulum salis JA746T (97.0). However, strain JA877T showed only 20-45 % relatedness with its phylogenetic neighbours and had a ∆Tm between 5.8 and 7.0 °C. The major respiratory quinone was ubiquinone-10 (Q10), and the polar lipid profile was composed of the major components phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, two unidentified sulfolipids and five unidentified lipids. The major fatty acids were C18 : 1ω5c, C18 : 1ω7c/C18 : 1ω6c, C16 : 0 and C18 : 0. The DNA G+C content was 64.5 mol%. On the basis of 16S rRNA gene sequence analysis, physiological data, and chemotaxonomic and molecular differences, strain JA877T is significantly different from other species of the genus Rhodovulum and represents a novel species, for which the name Rhodovulum algae sp. nov. is proposed. The type strain is JA877T (=LMG 29228T= KCTC 42963T).

Rhodovulum salis sp. nov. and Rhodovulum viride sp. nov., phototrophic Alphaproteobacteria isolated from marine habitats.

Two strains (JA746(T) and JA756(T)) having yellowish brown-to-green pigment were isolated from a solar saltern and a pink pond, respectively. While both strains were non-motile and shared the presence of bacteriochlorophyll-a, major cellular fatty acids (C18 : 1ω7c, C16 : 0, C18 : 0), quinone (Q-10), polar lipids and hopanoids, they differed from each other in their carotenoid composition. The G+C content of genomic DNA of strains JA746(T) and 756(T) was 62.4 and 63.3 mol%, respectively. The 16S rRNA gene-based EzTaxon-e blast search analysis of strains JA746(T) and 756(T) indicated highest sequence similarity with members of the genus Rhodovulum in the family Rhodobacteraceae of the class Alphaproteobacteria. Strain JA746(T) has high sequence similarities with Rhodovulum visakhapatnamense JA181(T) (97.3 %), Rhodovulum steppense A-20s(T) (97.3 %), Rhodovulum phaeolacus JA580(T) (97 %), Rhodovulum strictum MB-G2(T) (97 %) and other members of the genus Rhodovulum (<97 %). Strain JA756(T) has high sequence similarities with Rhodovulum visakhapatnamense JA181(T) (99.8 %), Rhodovulum sulfidophilum Hansen W4(T) (99.1 %), Rhodovulum kholense JA297(T) (97.9 %) and other members of the genus Rhodovulum (<97 %). The sequence similarity between strains JA746(T) and JA756(T) was 97.5 %. However, these strains are not closely related to each other or to their phylogenetic neighbours since the DNA-DNA reassociation values were less than 56 %. The genomic information was also supported by phenotypic and chemotaxonomic results, leading us to classify strains JA746(T) ( = NBRC 108898(T) = KCTC 15180(T)) and JA756(T) ( = NBRC 109122(T) = KCTC 15223(T)) as the type strains of two novel species of the genus Rhodovulum, for which the names Rhodovulum salis sp. nov. and Rhodovulum viride sp. nov. are proposed, respectively.