Paracoccus indicus sp. nov., isolated from surface seawater in the Indian Ocean.

Strain IO390502, isolated from surface seawater in the Indian Ocean, was characterised using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain IO390502 belongs to the genus Paracoccus and is closely related to Paracoccus seriniphilus DSM 14827 (97.6%), followed by P. zeaxanthinifaciens JCM 21774 (97.5%), P. homiensis DSM 17862 (97.3%), P. marcusii DSM 11574 (97.2%), P. haeundaensis BC 74171 (97.0%) and P. carotinifaciens E-396 (97.0%). Cells are Gram-negative, aerobic, poly-β-hydroxybutyrate-accumulating, motile, rod-shaped, and forms creamy-white colonies. Optimal growth occurred at 25-30 °C, pH 5-8, and in the presence of 3-8% NaCl. The genome of strain IO390502 has a G+C content of 64.9 mol% and a 3.5 Mb chromosome. The in silico DNA-DNA hybridisation and average nucleotide identity values between strain IO390502 and the three closely related taxa, P. seriniphilus DSM 14827, P. zeaxanthinifaciens JCM 21774 and P. homiensis DSM 17862, are 19.6%, 21.9% and 20.6%, and 76.0%, 79.9% and 77.8%, respectively. Phosphatidylglycerol is the major lipid present, ubiquinone-10 (Q-10) is the sole isoprenoid quinone, and the major cellular fatty acid is Cω7c. Based on data from phenotypic tests and genotypic differences between strain IO390502 and its close phylogenetic relatives, strain IO390502 represents a new species belonging to the genus Paracoccus, for which the name Paracoccus indicus sp. nov. is proposed. The type strain is IO390502 (= JCM 32637 = CCTCC AB 2018071).