Marinomonas algicola sp. nov. and Marinomonas colpomeniae sp. nov., isolated from marine macroalgae

Marinomonas rhodophyticola sp. nov. and Marinomonas phaeophyticola sp. nov., isolated from marine algae

Two Gram-stain-negative, facultatively aerobic, and motile rod bacteria, designated as strains KJ51-3T and 15G1-11T, were isolated from marine algae collected in the Republic of Korea. Both strains exhibited catalase- and oxidase-positive activities. Optimum growth conditions for strain KJ51-3T were observed at 30 °C and pH 6.0-8.0, with 1.0-7.0 % (w/v) NaCl, whereas strain 15G1-11T exhibited optimal growth at 30 °C, pH 7.0, and 1.0-5.0 % NaCl. Major fatty acids detected in both strains included C16 : 0, C10 : 0 3-OH and summed features 3 (C16 : 1  ω7c and/or C16 : 1  ω6c) and 8 (C18 : 1  ω7c and/or C18 : 1  ω6c). As for polar lipids, strain KJ51-3T contained phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol, and two unidentified phospholipids, whereas strain 15G1-11T had PE, PG, and an unidentified aminolipid. Ubiquinone-8 was the predominant respiratory quinone in both strains, with minor detection of ubiquinone-9 in strain KJ51-3T. The genomic DNA G+C contents were 44.0 mol% for strain KJ51-3T and 40.5 mol% for strain 15G1-11T. Phylogenetic analyses based on both 16S rRNA gene and genome sequences placed strains KJ51-3T and 15G1-11T into distinct lineages within the genus Marinomonas, most closely related to Marinomonas arctica 328T (98.6 %) and Marinomonas algicola SM1966T (98.3 %), respectively. Strains KJ51-3T and 15G1-11T exhibited a 94.6 % 16S rRNA gene sequence similarity and a 70.7 % average nucleotide identity (ANI), with ANI values of 91.9 and 79.3 % between them and M. arctica 328T and M. algicola SM1966T, respectively, indicating that they represent novel species. In summary, based on their phenotypic, chemotaxonomic, and phylogenetic properties, strains KJ51-3T and 15G1-11T are proposed to represent novel species within the genus Marinomonas, for which the names Marinomonas rhodophyticola sp. nov. (KJ51-3T=KACC 22756T=JCM 35591T) and Marinomonas phaeophyticola sp. nov. (15G1-11T=KACC 22593T=JCM 35412T) are respectively proposed.

Marinomonas transparens sp. nov. and Marinomonas sargassi sp. nov., isolated from marine alga

Two Gram-stain-negative, rod-shaped, non-spore-forming, strictly aerobic, motile bacteria with a single polar flagellum, designated strains C1424T and C2222T, were isolated from marine alga collected from the sea shore at Yantai, PR China. Strain C1424T grew at 4-37 °C and in the presence of 1-9 % (w/v) NaCl, while strain C2222T grew at 4-32 °C with 1-6 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and concatenated amino acid sequences of 120 ubiquitous single-copy proteins showed that both strains C1424T and C2222T belonged to the genus Marinomonas, showing highest 16S rRNA gene sequence similarities to the type strains of Marinomonas primoryensis (98.1 %) and Marinomonas dokdonensis (98.1 %), respectively. The major fatty acids of the two strains were C18 : 1  ω6c and/or C18 : 1  ω7c, C16 : 1  ω6c and/or C16 : 1  ω7c and C16 : 0, their predominant polar lipids were phosphatidylethanolamine and phosphatidylglycerol, and their sole respiratory quinone was Q8. On the basis of polyphasic analyses, strains C1424T and C2222T are considered to represent two novel species within the genus Marinomonas, for which the names Marinomonas transparens sp. nov. and Marinomonas sargassi sp. nov. are proposed. The type strains are C1424T (=KCTC 72119T=MCCC 1K03601T) and C2222T (=KCTC 72120T=MCCC 1K03602T), respectively.

Psychroserpens ponticola sp. nov. and Marinomonas maritima sp. nov., isolated from seawater

Two Gram-stain-negative, catalase- and oxidase-positive, aerobic non-motile and motile rod bacteria, strains MSW6T and RSW2T, were isolated from surface seawater. Strain MSW6T optimally grew at 20 °C, pH 7.0 and 3 % NaCl, while strain RSW2T optimally grew at 25 °C, pH 7.0-8.0 and 2 % NaCl. Strain MSW6T possessed menaquinone-6 as the major respiratory quinone, and its major fatty acids were iso-C15 : 1 G, iso-C15 : 0 and iso-C15 : 0 3-OH. The major polar lipid identified in strain MSW6T was phosphatidylethanolamine (PE). On the other hand, strain RSW2T had ubiquinone-8 as the predominant respiratory quinone, and its major fatty acids consisted of summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c), summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c) and C16 : 0. The major polar lipids identified in strain RSW2T were PE and phosphatidylglycerol. As the sole respiratory quinone, strain MSW6T possessed menaquinone-6, while strain RSW2T had ubiquinone-8. The DNA G+C contents of strains MSW6T and RSW2T were 31.9 and 43.4 mol%, respectively. Phylogenetic analyses based on 16S rRNA and core gene sequences showed that strain MSW6T formed a phylogenic lineage with Psychroserpens mesophilus KOPRI 13649T, while strain RSW2T formed a phylogenic lineage with Marinomonas primoryensis KMM 3633T. Strain MSW6T shared 97.9 % 16S rRNA gene sequence similarity and 80.7 % average nucleotide identity (ANI) ith P. mesophilus KOPRI 13649T, and strain RSW2T shared 99.1 % 16S rRNA gene sequence similarity and 93.1 % ANI with M. primoryensis KMM 3633T. Based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, strains MSW6T and RSW2T represent novel species of the genera Psychroserpens and Marinomonas, respectively, for which the names Psychroserpens ponticola sp. nov. and Marinomonas maritima sp. nov. are proposed, respectively. The type strain of P. ponticola is MSW6T (=KACC 22338T=JCM 35022T) and the type strain of M. maritima is RSW2T (=KACC 22716T=JCM 35550T).

Marinomonas lutimaris sp. nov., isolated from a tidal flat sediment of the East China Sea

A Gram-stain-negative bacterial strain, designated as E165T, was isolated from a tidal flat sediment of the East China Sea. Strain E165T grew optimally at pH 6, at 32 °C and with 1–2 % (w/v) NaCl. The 16S rRNA gene sequence similarity results revealed that strain E165T was most closely related to Marinomonas rhizomae IVIA-Po-145T, Marinomonas polaris CK13T, Marinomonas foliarum IVIA-Po-155T, Marinomonas hwangdonensis HDW-15T, Marinomonas pontica 46-16T, Marinomonas mangrovi B20-1T and Marinomonas shanghaiensis DSL-35T with values of 97.0–98.5 %. The digital DNA–DNA hybridization and average nucleotide identity values between strain E165T and the reference strains were 21.9–34.3 % and 77.6–87.3 %, respectively. The DNA G+C content of the isolate was 42.9 mol%. Strain E165T contained Q-8 as the sole ubiquinone and C16 : 0, summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c) and summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c) as the major fatty acids. The major polar lipids of strain E165T were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, aminolipid and aminophospholipid. On the basis of phenotypic characteristics, phylogenetic analysis and DNA–DNA relatedness, a novel species, Marinomonas lutimaris sp. nov., is proposed with E165T (=MCCC 1K06241T=KCTC 82809T) as the type strain.