Devosia marina sp. nov., isolated from deep seawater of the South China Sea, and reclassification of Devosia subaequoris as a later heterotypic synonym of Devosia soli

Abstract

A Gram-stain-negative, aerobic, rod-shaped and motile bacterial strain, designated L53-10-65T, was isolated from deep seawater of the South China Sea. Strain L53-10-65T was found to grow at 4–41 °C (optimum, 28 °C), at pH 5.0–9.0 (pH 7.0–8.0) and in 0–7 % (w/v) NaCl (2 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain L53-10-65T fell within the genus Devosia , with the highest similarity to Devosia indica IO390501T (98.4 %), followed by ‘ Devosia lucknowensis ’ L15T (97.7 %) and Devosia riboflavina IFO 13584T (96.8 %). The digital DNA–DNA hybridization (dDDH) values between strain L53-10-65T and the three relatives above were 43.7, 21.5 and 20.9 %, respectively; the average nucleotide identity (ANI) values were 91.3, 78.4 and 76.8 %, respectively. These values were below the 70 % dDDH and 95–96 % ANI thresholds for bacterial species delineation. The major cellular fatty acids of strain L53-10-65T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), C18 : 1 ω7c 11-methyl and C16 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and glycolipids. The respiratory quinone was identified as Q-10. The DNA G+C content of strain L53-10-65T was 61.3 mol%. Based on the results of phylogenetic analysis and distinctive phenotypic characteristics, strain L53-10-65T is concluded to represent a novel species of the genus Devosia , for which the name Devosia marina sp. nov. is proposed. The type strain of the species is L53-10-65T (=MCCC 1A05139T=KCTC 72888T). Moreover, we propose that Devosia subaequoris is a later heterotypic synonym of Devosia soli based on the present results.