Afifella aestuarii sp. nov., a phototrophic bacterium

An oval- to rod-shaped, motile, Gram-stain-negative, oxidase-positive, catalase-negative, pink-coloured phototrophic bacterium (designated as strain JA968^T) was isolated from an estuary near Pata, Gujarat, India. Cells had an intracytoplasmic membrane architecture as lamellae and divided by budding. Strain JA968^T had bacteriochlorophyll-a and spirilloxanthin series carotenoids as photosynthetic pigments. The strain exhibited photolithoautotrophic, photoorganoheterotrophic and chemoorganoheterotrophic growth modes and required thiamine as a growth factor. Strain JA968^T had C_18 : 1ω7c/C_{18  : 1}ω6c as the predominant fatty acid with ubiquinone-10 (Q-10) and menaquinone-10 (MK-10) forming the quinone composition. The genomic DNA G+C content of the strain was 63.5 mol%. Pairwise comparison of 16S rRNA gene sequences showed that strain JA968^T was highly similar to Afifella marina DSM 2698^T (99.9 %) and Afifella pfennigii DSM 17143^T (98.4 %). The average nucleotide identity values were 92 % between strain JA968^T and A. marina DSM 2698^T, and 78 % between strain JA968^T and A. pfennigii DSM 17143^T. The digital DNA-DNA hybridization values between strain JA968^T and A. marina and A. pfennigii were 49 and 19 %, respectively. The genomic distinction was also supported by differences in phenotypic and chemotaxonomic characteristics. We propose that strain JA968^T represents a new species of the genus Afifella with the name Afifella aestuarii sp. nov. The type strain is JA968^T (=KCTC 15634^T=NBRC 113338^T).