Rheinheimera lutimaris sp. nov., a marine bacterium isolated from coastal sediment

Rheinheimera oceanensis sp. nov., a novel member of the genus Rheinheimera, isolated from the West Pacific Ocean

Two Gram-stain-negative, aerobic, non-motile and short-rod-shaped bacteria, designated as strains GL-53T and GL-15-2-5, were isolated from the seamount area of the West Pacific Ocean and identified using a polyphasic taxonomic approach. The growth of strains GL-53ᵀ and GL-15-2-5 occurred at pH 5.5-10.0, 4-40 °C (optimum at 28 °C) and 0-10.0 % NaCl concentrations (optimum at 0-5.0 %). On the basis of 16S rRNA gene sequence analysis, strains GL-53ᵀ and GL-15-2-5 exhibited the highest similarity to Rheinheimera lutimaris YQF-2T (98.4 %), followed by Rheinheimera pacifica KMM 1406T (98.1 %), Rheinheimera nanhaiensis E407-8T (97.4 %), Rheinheimera aestuarii H29T (97.4 %), Rheinheimera hassiensis E48T (97.2 %) and Rheinheimera aquimaris SW-353T (97.2 %). Phylogenetic analysis revealed that the isolates were affiliated with the genus Rheinheimera and represented an independent lineage. The major fatty acids were summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c), C16 : 0 and summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c). The sole isoprenoid quinone was ubiquinone 8. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid (and one unidentified glycolipid. The DNA G+C content was 48.5 mol%. The average nucleotide identity, average amino acid identity and in silico DNA-DNA hybridization values among the genomes of strain GL-53ᵀ and the related strains in the genus Rheinheimera were 75.5-90.1 %, 67.5-93.9 % and 21.4-41.4 %, respectively. Based on their phenotypic, chemotaxonomic and genotypic properties, the two strains were identified as representing a novel species of the genus Rheinheimera, for which the name Rheinheimera oceanensis sp. nov. is proposed. The type strain is GL-53T (=KCTC 82651T=MCCC M20598T).

Rheinheimera maricola sp. nov., isolated from seawater of the Yellow Sea

A Gram-negative and facultative aerobic strain, designated as strain MA-13T, was isolated from seawater in the Yellow Sea Republic of Korea. Cells were oxidase- and catalase-positive and non-motile short rods. Growth of strain MA-13T was observed over a range of 10–37 °C (optimum, 30 °C), pH 6.0–11.0 (optimum, pH 7.0) and in the presence of 0–5.5 % (w/v) sodium chloride (optimum, 1.0–2.0 %). Strain MA-13T contained ubiquinone-8 as the respiratory quinone, phosphatidylethanolamine, an unidentified aminolipid, an unidentified phospholipid and four unidentified lipids as major polar lipids and C16 : 0, C12 : 0 3-OH and summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c) as major cellular fatty acids. The G+C content of the genomic DNA was 48.3 mol%. Phylogenetic analyses based on the 16S rRNA gene and whole-genome sequences revealed that strain MA-13T formed a distinct phyletic lineage in the genus Rheinheimera . Strain MA-13T was most closely related to Rheinheimera lutimaris YQF-2T, Rheinheimera aquimaris SW-353T, Rheinheimera pacifica KMM 1406T and Rheinheimera baltica DSM 14885T with 98.10, 98.08, 98.07 and 97.94 % 16S rRNA gene sequence similarities. Average nucleotide identity and DNA–DNA hybridization values between strain MA-13T and R. aquimaris KCTC 12840T, R. pacifica DSM 17616T and R. baltica DSM 14885T were 76.3, 78.6 and 76.9 % and 19.5, 21.3 and 20.5 %, respectively. Based on the phenotypic, chemotaxonomic and molecular features, strain MA-13T represents a novel species of the genus Rheinheimera , for which the name Rheinheimera maricola sp. nov. is proposed. The type strain is MA-13T (=KACC 22113T=JCM 34600T).