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.

Marinomonas vulgaris sp. nov., a marine bacterium isolated from seawater in a coastal intertidal zone of Zhoushan island

A Marinomonas-like, Gram-stain-negative, strictly aerobic and rod to ovoid-shaped bacterium, designated as strain A79^T, was isolated from the seawater mixtures of oyster shells and brown algae in a coastal intertidal zone of Zhoushan, China. The strain was positive for oxidase and catalase. Colonies grown on marine agar for 48 h were round, milky white, smooth and moist with the diameter of 2-3 mm. Growth was observed at 15-30 °C (optimum, 25℃), pH 5.5-9.5 (optimum, pH 8.5) and with 0.5-8% (w/v) NaCl (optimum, 2-2.5%). The G + C content based on the genome sequence was 46.0%. The only respiratory quinone was Q-8. The main polar lipids contained phosphatidylglycerol, phosphatidylethanolamine, unidentified glycolipids, unidentified phospholipid and three unidentified lipids. The major fatty acids (> 10%) were C_16:0, Summed feature 3 (comprising C_16:1 ω6c and/or C_16:1 ω7c) and summed feature 8 (comprising C_18:1 ω6c and/or C_18:1 ω7c). The 16S rRNA gene sequence similarity between strain A79^T and Marinomonas pollencensis IVIA-Po-185^T was 97.4%, the similarities with other type strains of the genus Marinomonas were 93.8-96.7%. Based on the results, Marinomonas vulgaris sp. nov. was proposed as a novel species. The type strain is A79^T (= MCCC 1K05799^T = KCTC 82519^T = JCM 34473^T).

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

Two Gram-stain-negative, aerobic, rod-shaped bacteria, polar flagellated, designated strains SM2066^T and SM1966^T, were respectively isolated from the surfaces of Colpomenia sinuosa and Ulva pertusa macroalgae collected off the coastal areas of Rongcheng, PR China. Strain SM2066^T grew at 8-37 °C and with 0.5-7.0 % (w/v) NaCl, while strain SM1966^T grew at 5-30 °C and with 0.5-8.5% (w/v) NaCl. Both of them reduced nitrate to nitrite and required Na⁺ for growth but neither of them hydrolysed starch and DNA. Phylogenetic analysis based on 16S rRNA gene and single-copy orthologous cluster sequences revealed that both strains SM2066^T and SM1966^T were affiliated with the genus Marinomonas but formed distinct phylogenetic branches from known Marinomonas species, respectively sharing the highest 16S rRNA gene sequence similarities with type strains of Marinomonas ushuaiensis (97.9 %) and Marinomonas blandensis (96.7 %). The digital DNA-DNA hybridization and average nucleotide identity values between strains SM2066^T and SM1966^T and type strains of closely related Marinomonas species were all below 22.9 and 79.9 mol%, respectively. The major fatty acids of the two strains were summed feature 3 (C_16 : 1  ω6c/C_16 : 1  ω7c), summed feature 8 (C_18 : 1  ω7c) and C_16 : 0, with their predominant polar lipids being phosphatidylethanolamine and phosphatidylglycerol, and their sole respiratory quinone being Q-8. The genomic DNA G+C contents of strains SM2066^T and SM1966^T determined from genomic sequences were 40.3 and 41.6 mol%, respectively. On the basis of the polyphasic evidence presented in this study, strains SM2066^T and SM1966^T are considered to represent two novel species within the genus Marinomonas, for which the names Marinomonas colpomeniae sp. nov. and Marinomonas algicola sp. nov. are proposed. The type strains are SM2066^T (=MCCC 1K04390^T= KCTC 82372^T) and SM1966^T (=MCCC 1K04387^T= KCTC 72848^T), respectively.