Hyphomonas sediminis sp. nov., isolated from marine sediment.

A Gram-staining-negative, aerobic and pear-shaped bacterial strain, designated WL0036, was isolated from coastal sediment sample collected in Nantong city, Jiangsu province of China (120° 51' 13″ E, 32° 6' 26″ N) in October 2020. Strain WL0036 was found to grow at 20-37 °C (optimum, 28 °C) with 0-9.0% NaCl (optimum, 2.5-4.0%) and displayed alkaliphilic growth with the pH range of pH 6.0-10.0 (optimum, pH 7.0-8.0). The polar lipids profile of strain WL0036 included phosphatidylcholine, phosphatidylethanolamine, glycolipid and an unidentified lipid. The major isoprenoid quinone was determined to be Q-11 and the major fatty acids were C, 11-methyl-Cω7c, and summed features 8 (Cω6c and/or Cω7c). The G + C content of genomic DNA was 61.8%. Phylogenetic trees constructed based on 16S rRNA gene sequence and bac120 gene set (a collection of 120 single-copy protein sequences prevalent in bacteria) indicted that strain WL0036 clustered with strains Hyphomonas neptunium ATCC 15444 and H. polymorpha PS728. The average nucleotide identities between strain WL0036 and strains H. neptunium ATCC 15444 and H. polymorpha PS728 were 80.7% and 81.2%, respectively. Strain WL0036 showed 22.8% and 23.2% of digital DNA-DNA hybridization identities with H. neptunium ATCC 15444 and H. polymorpha PS728, respectively. As inferred from the phenotypic and genotypic characteristics and the phylogenetic trees, strain WL0036 ought to be recognized as a novel species in genus Hyphomonas, for which the name Hyphomonas sediminis sp. nov. is proposed. The type strain is WL0036 (= MCCC 1K05843 = JCM 34658 = GDMCC 1.2413).