No abstract

The chemical analysis of a Streptomyces strain, from a Korean volcanic island, discovered new benz­[a]­anthracene dimers linked by a thioether bond. The structures of donghaesulfins A and B (1 and 2) were elucidated by spectroscopic analysis including energy-dispersive X-ray. Their configurations were determined by ROESY NMR data, DP4 calculations, the modified Mosher’s method, and ECD calculations. Donghaesulfins A (1) induced quinone reductase, whereas donghaesulfin B (2) displayed antiangiogenesis activity.

A Gram-stain-negative, rod-shaped, aerobic, non-flagellated, chemoheterotrophic bacterium, designated IMCC14385T, was isolated from surface seawater of the East Sea, Republic of Korea. The 16S rRNA gene sequence analysis indicated that IMCC14385T represented a member of the genus Halioglobus sharing 94.6–97.8 % similarities with species of the genus. Whole-genome sequencing of IMCC14385T revealed a genome size of 4.3 Mbp and DNA G+C content of 56.7 mol%. The genome of IMCC14385T shared an average nucleotide identity of 76.6 % and digital DNA–DNA hybridization value of 21.6 % with the genome of Halioglobus japonicus KCTC 23429T. The genome encoded the complete poly-β-hydroxybutyrate biosynthesis pathway. The strain contained summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and C17 : 1 ω8c as the predominant cellular fatty acids as well as ubiquinone-8 (Q-8) as the respiratory quinone. The polar lipids detected in the strain were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, five unidentified phospholipids, an unidentified aminolipid, an unidentified aminophospholipid and four unidentified lipids. On the basis of taxonomic data obtained in this study, it is suggested that IMCC14385T represents a novel species of the genus Halioglobus , for which the name Halioglobus maricola sp. nov. is proposed. The type strain is IMCC14385T (=KCTC 72520T=NBRC 114072T).

The genus Kordia is one of many genera affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes, well known for its degradation of high molecular weight organic matters. The genus Kordia currently comprises eight species, type strains of which have been isolated from a diverse range of marine environments. As of this report, four genome sequences have been submitted for cultured strains of Kordia, but none are complete nor have they been analyzed comprehensively. In this study, we report the complete genome of Kordia antarctica IMCC3317T, isolated from coastal seawater off the Antarctic Peninsula. The complete genome of IMCC3317T consists of a single circular chromosome with 5.5 Mbp and a 33.2 mol% of G+C DNA content. The IMCC3317T genome showed features typical of chemoheterotrophic marine bacteria and similar to other Kordia genomes, such as complete gene sets for the Embden–Meyerhof–Parnas glycolysis pathway, tricarboxylic acid cycle and oxidative phosphorylation. The genome also encoded many carbohydrate-active enzymes, some of which were clustered into approximately seven polysaccharide utilization loci, thereby demonstrating the potential for polysaccharide utilization. Finally, a nosZ gene encoding nitrous oxide reductase, an enzyme that catalyzes the reduction of N2O to N2 gas, was also unique to the IMCC3317T genome.

Two new secondary metabolites, svalbamides A (1) and B (2), were isolated from a culture extract of Paenibacillus sp. SVB7 that was isolated from surface sediment from a core (HH17-1085) taken in the Svalbard archipelago in the Arctic Ocean. The combinational analysis of HR-MS and NMR spectroscopic data revealed the structures of 1 and 2 as being lipopeptides bearing 3-amino-2-pyrrolidinone, d-valine, and 3-hydroxy-8-methyldecanoic acid. The absolute configurations of the amino acid residues in svalbamides A and B were determined using the advanced Marfey’s method, in which the hydrolysates of 1 and 2 were derivatized with l- and d- forms of 1-fluoro-2,4-dinitrophenyl-5-alanine amide (FDAA). The absolute configurations of 1 and 2 were completely assigned by deducing the stereochemistry of 3-hydroxy-8-methyldecanoic acid based on DP4 calculations. Svalbamides A and B induced quinone reductase activity in Hepa1c1c7 murine hepatoma cells, indicating that they represent chemotypes with a potential for functioning as chemopreventive agents.

Two Gram-stain-negative, Fe(III)-reducing, facultatively anaerobic, motile via a single polar flagellum, rod-shaped bacterial strains, designated IMCC35001T and IMCC35002T, were isolated from tidal flat sediment and seawater, respectively. Results of 16S rRNA gene sequence analysis showed that IMCC35001T and IMCC35002T shared 96.6 % sequence similarity and were most closely related to Ferrimonas futtsuensis FUT3661T (98.6 %) and Ferrimonas kyonanensis Asr22-7T (96.8 %), respectively. Draft genome sequences of IMCC35001T and IMCC35002T revealed 4.0 and 4.8 Mbp of genome size with 61.0 and 51.8 mol% of DNA G+C content, respectively. Average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between the two strains were 73.1 and 19.8 %, respectively, indicating that they are separate species. The two genomes showed ≤84.4 % ANI and ≤27.8 % dDDH to other species of the genus Ferrimonas , suggesting that the two strains each represent novel species. The two strains contained both menaquinone (MK-7) and ubiquinones (Q-7 and Q-8). Major fatty acids of strain IMCC35001T were iso-C15 : 0, C18 : 1  ω9c, C17 : 1  ω8c and C16 : 0 and those of strain IMCC35002 T were C18 : 1  ω9c, C16 : 0 and summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c). Major polar lipids in both strains were phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid, unidentified aminophospholipid and unidentified lipids. The two strains reduced Fe(III) citrate, Fe(III) oxyhydroxide, Mn(IV) oxide and sodium selenate but did not reduce sodium sulfate. They were also differentiated by several phenotypic characteristics. Based on the polyphasic taxonomic data, IMCC35001T and IMCC35002T were considered to represent each novel species in the genus Ferrimonas , for which the names Ferrimonas sediminicola sp. nov. (IMCC35001T=KACC 21161T=NBRC 113699T) and Ferrimonas aestuarii (IMCC35002T=KACC 21162T=NBRC 113700T) sp. nov. are proposed.

A Gram-stain-negative, short-rod, facultatively anaerobic, non-motile and red-pigmented bacterium, designated SAORIC-165, was isolated from a deep-seawater sample collected from the Pacific Ocean. The 16S rRNA gene sequence analysis showed that strain SAORIC-165 was most closely related to Rubritalea marina Pol012 (95.7 % sequence similarity) and formed a robust phylogenetic clade with other species of the genus Rubritalea in the phylum Verrucomicrobia. Optimal growth of strain SAORIC-165 was observed at 10 °C, pH 7.0 and in the presence of 2.0-3.5 % (w/v) NaCl. The DNA G+C content of strain SAORIC-165 was 50.7 mol% and MK-9 was the predominant isoprenoid quinone. The major cellular fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C14 : 0, anteiso-C15 : 0, C16 : 0 and C14 : 0. The major polar lipids constituted phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and unidentified phospholipids and aminolipids. On the basis of the taxonomic data obtained in this study, it was concluded that strain SAORIC-165 represented a novel species of the genus Rubritalea, for which the name Rubritalea profundi sp. nov. is proposed. The type strain of Rubritalea profundi is SAORIC-165 (=NBRC 110691=KCTC 52460).

A Gram-stain-negative, non-flagellated, motile-by-gliding, orange-coloured bacterial strain, designated strain IMCC20180, was isolated from seawater collected off the coast of the East Sea in the Republic of Korea. The 16S rRNA gene sequence analysis showed that strain IMCC20180 was most closely related to Winogradskyellaporiferorum UST030701-295 (95.7 % sequence similarity) and formed a robust phylogenetic clade with other Winogradskyella species, indicating that the strain was affiliated with the genus Winogradskyella. Growth of strain IMCC20180 was observed at 20-30 °C (optimum, 25 °C), pH 7.0-9.0 (pH 8.0) and with 1.0-3.5 % NaCl (3.0 %, w/v). The predominant isoprenoid quinone was MK-6. Major fatty acid constituents were iso-C15 : 1 G, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), iso-C15 : 0, iso-C17 : 0 3-OH and iso-C16 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, four unknown aminolipids and five unknown lipids. The estimated genome size and the DNA G+C content of strain IMCC20180 were 3.1 Mb and 37.7 %, respectively. Based on 16S rRNA gene phylogeny, physiological and chemotaxonomic characterization, strain IMCC20180 represented a novel species in the genus Winogradskyella, for which the name Winogradskyellaaurantiaca sp. nov. is proposed. The type strain is IMCC20180 (=KACC 18883=KCTC 52240=JCM 31383).