RESUMEN
Random mutagenesis for the hyperthermophilic archaeon Thermococcus kodakarensis was established by the insertion of an artificial transposon designed to allow easy identification of the transposon-inserted locus. The phenotypic screening was applied for the isolation of thermosensitive mutants of T. kodakarensis, which resulted in the isolation of 16 mutants showing defective growth at the supraoptimal temperature 93°C. The high occurrence of the mutants suggested that the high thermotolerance of hyperthermophiles was achieved by a combination of diverse gene functions. The transposon insertion sites in two-thirds of the mutants were identified in a group of genes responsible for tRNA modifications including 7-formamidino-7-deaza-guanosine (archaeosine), N1-methyladenosine/N1-methylinosine, N4-acetylcytidine, and N2-dimethylguanosine/N2,N2-dimethylguanosine. LC-MS/MS analyses of tRNA nucleosides and fragments exhibited disappearance of the corresponding modifications in the mutants. The melting temperature of total tRNA fraction isolated from the mutants lacking archaeosine or N1-methyladenosine/N1-methylinosine decreased significantly, suggesting that the thermosensitive phenotype of these mutants was attributed to low stability of the hypomodified tRNAs. Genes for metabolism, transporters, and hypothetical proteins were also identified in the thermosensitive mutants. The present results demonstrated the usefulness of random mutagenesis for the studies on the hyperthermophile, as well as crucial roles of tRNA modifications in cellular thermotolerance.
Asunto(s)
Guanosina/análogos & derivados , Mutagénesis/genética , ARN de Transferencia/genética , Thermococcus/genética , Secuencia de Bases , Cromatografía Liquida , Regulación de la Expresión Génica Arqueal , Guanosina/química , Guanosina/genética , Nucleósidos/química , Nucleósidos/genética , Espectrometría de Masas en Tándem , TemperaturaRESUMEN
Jasmonates regulate plant defense and development. In Arabidopsis (Arabidopsis thaliana), JASMONATE-ASSOCIATED VQ-MOTIF GENE1 (JAV1/VQ22) is a repressor of jasmonate-mediated defense responses and is degraded through the ubiquitin-26S proteasome system after herbivory. We found that JAV1-ASSOCIATED UBIQUITIN LIGASE1 (JUL1), a RING-type E3 ubiquitin ligase, interacted with JAV1. JUL1 interacted with JAV1 in the nucleus to ubiquitinate JAV1, leading to proteasomal degradation of JAV1. The transcript levels of JUL1 and JAV1 were coordinately and positively regulated by the CORONATINE INSENSITIVE1-dependent signaling pathway in the jasmonate signaling network, but in a manner that was not dependent on CORONATINE INSENSITIVE1-mediated signaling upon herbivory by Spodoptera litura Gain or loss of function of JUL1 modulated the expression levels of the defensin gene PDF1.2 in leaves, conferring on the plants various defense properties against the generalist herbivore S. litura Because neither the JUL1 mutant nor overexpression lines showed any obvious developmental defects, we concluded that the JAV1/JUL1 system functions as a specific coordinator of reprogramming of plant defense responses. Altogether, our findings offer insight into the mechanisms by which the JAV1/JUL1 system acts specifically to coordinate plant defense responses without interfering with plant development or growth.
Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Arabidopsis/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
A Gram-stain-negative, strictly aerobic, pale-yellow pigmented, rod-shaped, chemoheterotrophic bacterium, designated A6F-11(T), was isolated from a marine sponge collected in Japan. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the novel marine strain was affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes and that it shared the highest (92.9 %) sequence similarity with Arenibacter palladensis LMG 21972(T). The strain could be differentiated phenotypically from related members of the family Flavobacteriaceae. The major fatty acids of strain A6F-11(T) were iso-C15:1 G, iso-C15:0, C16:1 ω6c and/or C16:1 ω7c and iso-C17:0 3-OH. The polar lipid profile consisted of phosphatidylglycerol, two unidentified aminolipids and two unidentified lipids. The DNA G+C content was 34.7 mol%, and the major respiratory quinone was menaquinone 6 (MK-6). From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel taxon in the family Flavobacteriaceae, for which the name Spongiimicrobium salis gen. nov., sp. nov. is proposed. The type strain of S. salis gen. nov., sp. nov. is A6F-11(T) (= KCTC 42753(T) = NBRC 111401(T)).
Asunto(s)
Flavobacteriaceae , Poríferos/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base/genética , ADN Bacteriano/genética , Ácidos Grasos/análisis , Flavobacteriaceae/clasificación , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Japón , Fosfatidiletanolaminas/análisis , Fosfolípidos/análisis , Filogenia , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/análisisRESUMEN
A Gram-stain-negative, rod-shaped, non-motile, strictly aerobic, chemoheterotrophic, pale-yellow-pigmented bacterium, designated strain A6D-50T, was isolated from an ascidian collected at Kohama Island offshore Okinawa, Japan. Preliminary analysis based on the 16S rRNA gene sequence revealed that the novel isolate was affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes and that it showed highest sequence similarity (97.6 %) to Aureisphaera galaxeae 04OKA003-7T. The DNA-DNA relatedness value between strain A6D-50T and A. galaxeae 04OKA003-7T was 23.6 %. The DNA G+C content of strain A6D-50T was 40.8 mol%, MK-6 was the only menaquinone, and iso-C17 : 0 3-OH, iso-C15 : 0, iso-C15 : 1 G and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) were the major (>10 %) cellular fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, two unidentified aminolipids and an unidentified lipid. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel species of the genus Aureisphaera for which the name Aureisphaera salina sp. nov. is proposed. The type strain is A6D-50T (= KCTC 42975T=NBRC 111827T).
Asunto(s)
Flavobacteriaceae/clasificación , Filogenia , Urocordados/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Japón , Hibridación de Ácido Nucleico , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A Gram stain-negative, strictly aerobic, brown-pigmented, non-motile, rod-shaped, chemoheterotrophic bacterial strain-designated A6F-119(T) was isolated from a marine sponge (Rhabdastrella sp.). Phylogenetic analyses based on the 16S rRNA gene sequence revealed that the new strain represented a member of the family Flavobacteriaceae of the phylum Bacteroidetes and that it showed highest sequence similarity (93 %) to Tenacibaculum maritimum NBRC 15946(T). The strain could be differentiated phenotypically from the recognized members of the family Flavobacteriaceae. The DNA G + C content of strain A6F-119(T) was determined to be 30.8 mol%; MK-6 was identified as the major menaquinone; and the presence of iso-C15:0, iso-C17:0 3-OH, and C16:1 ω7c and/or C16:1 ω6c as the major (>10 %) cellular fatty acids. A polar lipid profile was present consisting of phosphatidylethanolamine, an unidentified aminolipid, and three unidentified lipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus for which the name Spongiiferula fulva gen. nov., sp. nov. is proposed. The type strain of S. fulva is A6F-119(T) (= KCTC 42752(T) = NBRC 111402(T)).
Asunto(s)
Flavobacteriaceae/aislamiento & purificación , Poríferos/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Flavobacteriaceae/clasificación , Flavobacteriaceae/genética , Flavobacteriaceae/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Agua de Mar/microbiologíaRESUMEN
Phylogenetic and taxonomic characterization was performed for a bacterium, designated strain Q-192T, isolated from the surface of the green macroalga Halimeda sp., collected from the subtropical Ishigaki Island, Japan. The isolate was a polysaccharide-producing, Gram-stain-negative, aerobic, rod-shaped, motile bacterium with a polar flagellum. The isolate was slightly halophilic, required Na+, Mg2+ and Ca2+ ions for growth, but did not require growth factors. The only isoprenoid quinone was ubiquinone-8.The major cellular fatty acids were C18 : 1ω7c, C16 : 0 and C14 : 0. The main hydroxy fatty acid was C10 : 0 3-OH. The DNA G+C content was 45.9âmol%. Phylogenetic analysis of 16S rRNA gene sequences placed the isolate in the class Gammaproteobacteria. The phylogenetically closest relatives with validly published names were Pseudomaricurvus alkylphenolicus KU41GT, Teredinibacter turnerae T7902T, Pseudoteredinibacter isoporae SW-11T and Simiduia agarivorans SA1T with sequence similarities of 94.5, 94.1, 93.7 and 93.6 %, respectively. The isolate was distinguished from members of these genera by a combination of DNA G+C content, chemotaxonomic characteristics (respiratory quinone system, fatty acid profile and polar lipid composition) and other phenotypic features. Based on phylogenetic, genotypic, chemotaxonomic and phenotypic characteristics, strain Q-192T is considered to represent a novel species of a new genus, for which the name Marinibactrum halimedae gen. nov., sp. nov. is proposed. The type strain of Marinibactrum halimedae is Q-192T ( = NBRC 110095T = NCIMB 14932T).
RESUMEN
A facultatively anaerobic, Gram-stain negative, golden-yellow pigmented, non-motile and rod-shaped bacterium, designated strain A5Q-67(T) was isolated from leaf litter collected at the mangrove estuary of Nakama River, Japan. Phylogenetic analysis based on the 16S rRNA gene sequence revealed the novel isolate was affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes and that it showed highest sequence similarity (94.2 %) to Imtechella halotolerans K1(T). The strain could be differentiated phenotypically from recognized members of the family Flavobacteriaceae. The major fatty acids of strain A5Q-67(T) were identified as iso-C17:0 3-OH, summed feature 1 (iso-C15:1 H and/or C13:0 3-OH) and iso-C15:0 as defined by the MIDI system. The DNA G+C content was determined to be 36.7 mol%, the major respiratory quinone was identified as menaquinone 6 (MK-6) and a polar lipid profile was present consisting of phosphatidylethanolamine, two unidentified aminolipids and an unidentified lipid. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus for which the name Frondibacter aureus gen. nov., sp. nov. is proposed. The type strain of F. aureus is A5Q-67(T) (=KCTC 32991(T) = NBRC 110021(T)).
Asunto(s)
Microbiología Ambiental , Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Aerobiosis , Anaerobiosis , Organismos Acuáticos/clasificación , Organismos Acuáticos/genética , Organismos Acuáticos/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Flavobacteriaceae/genética , Japón , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Fosfolípidos/análisis , Filogenia , Pigmentos Biológicos , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análisisRESUMEN
A polyphasic taxonomic investigation was performed on a bacterial strain, 38-Ka-2(T), which was isolated from the green alga Ulva pertusa Kjellman (Chlorophyta) in Hokkaido, Japan. The bacterial cells were observed to be golden-yellow coloured, Gram-negative, strictly aerobic, non-spore-forming, non-motile and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain is a member of the family Flavobacteriaceae within the phylum Bacteroidetes and that it shows high sequence similarity (94.8 %) to Aquimarina addita JC2680(T). The genomic DNA G+C content of strain 38-Ka-2(T) was determined to be 36 mol%; MK-6 was identified as the major menaquinone; and the presence of iso-C15:0, C18:0 and iso-C17:0 3-OH as the major (>10 %) cellular fatty acids. The polar lipid profile was found to consist of phosphatidylethanolamine, an unidentified glycolipid and two unidentified lipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, strain 38-Ka-2(T) is considered to represent a novel genus for which the name Algitalea ulvae gen. nov., sp. nov. is proposed. The type strain of A. ulvae is 38-Ka-2(T) (=KCTC 32994(T) = NBRC 110017(T)).
Asunto(s)
Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Ulva/microbiología , Aerobiosis , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Flavobacteriaceae/genética , Flavobacteriaceae/fisiología , Glucolípidos/análisis , Japón , Locomoción , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Fosfolípidos/análisis , Filogenia , Pigmentos Biológicos/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análisisRESUMEN
A Gram-negative, strictly aerobic, lemon-yellow pigmented, non-motile, rod-shaped strain designated A7G-39(T) was isolated from a yellow coloured marine sponge (Tethya sp.). Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain represented a member of the family Flavobacteriaceae of the phylum Bacteroidetes and that it showed highest sequence similarity (94.1 %) to Algibacter wandonensis WS-MY22(T). The strain could be differentiated phenotypically from recognised members of the family Flavobacteriaceae. The major fatty acids of strain A7G-39(T) were identified as iso-C15:0 3-OH and summed feature 1 (iso-C15:1 H and/or C13:0 3-OH) as defined by the MIDI system. The DNA G+C content was determined to be 32.6 mol%, the major respiratory quinone was identified as menaquinone 7 (MK-7) and a polar lipid profile was present consisting of phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus for which the name Spongiivirga citrea gen. nov., sp. nov. is proposed. The type strain of S. citrea is A7G-39(T) (=KCTC 32990(T) = NBRC 110022(T)).
Asunto(s)
Flavobacteriaceae/aislamiento & purificación , Poríferos/microbiología , Agua de Mar/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/metabolismo , Flavobacteriaceae/clasificación , Flavobacteriaceae/genética , Flavobacteriaceae/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
A Gram-negative, strictly aerobic, pale-yellow pigmented, rod-shaped bacterium designated A4O-5(T) was isolated from a red coloured marine alga (Chondrus ocellatus Holmes). Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain was affiliated with the family Flavobacteriaceae and shared approximately 90 % sequence similarity with Leptobacterium flavescens YM3-0301(T) and Gangjinia marincola GJ16(T). The strain could be differentiated phenotypically from the related members of the family Flavobacteriaceae. The major fatty acids of strain A4O-5(T) were identified as iso-C15:0, iso-C17:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). A complex polar lipid profile was present consisting of phosphatidylethanolamine, an unidentified phospholipid, three unidentified amino lipids and an unidentified lipid. The DNA G+C content of the strain was determined to be 41.9 mol% and the major respiratory quinone was identified as menaquinone 6 (MK-6). From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus in the family Flavobacteriaceae, for which the name Citreitalea marina gen. nov., sp. nov. is proposed. The type strain of C. marina is A4O-5(T) (=KCTC 32483(T)=NBRC 109918(T)).
Asunto(s)
Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Rhodophyta/microbiología , Aerobiosis , Organismos Acuáticos/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Chondrus , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Flavobacteriaceae/genética , Flavobacteriaceae/fisiología , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Fosfolípidos/análisis , Filogenia , Pigmentos Biológicos , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Two non-motile, rod-shaped gammaproteobacteria were isolated from marine sponges collected from the coast of Japan at Numazu. The isolates were oxidase- and catalase-positive facultative anaerobes that fermented carbohydrates. They required sodium ions for growth and were slightly halophilic, growing in the presence of 1.0-5.0â% (w/v) NaCl (optimum of 2.0â% NaCl). Under aerobic conditions, the major isoprenoid quinones were ubiquinone-9 and menaquinone-9 and the minor quinones were ubiquinone-8 and menaquinone-8. The major cellular fatty acids were C(18â:â1)ω7c, C(16â:â1)ω7c and C(16â:â0) and the hydroxy acids were C(10â:â0) 3-OH and C(12â:â0) 3-OH. The DNA G+C content was 48.3-48.7 mol%. Phylogenetic analysis of 16S rRNA gene sequences placed the isolates within the radiation of the genus Endozoicomonas in a broad clade of uncultured clones recovered from various marine invertebrates. The isolates exhibited 96.5-96.9â% 16S rRNA gene sequence similarity with Endozoicomonas elysicola MKT110(T) and Endozoicomonas montiporae CL-33(T), with which the isolates formed a monophyletic cluster with 100â% bootstrap support. The phenotypic features (carbohydrate fermentation, quinone system and some major cellular fatty acids) differed from those of members of the genus Endozoicomonas, which are aerobic, produce little or no menaquinone under aerobic conditions and possess different amounts of C(14â:â0) and C(18â:â1)ω7c. Although some phenotypic differences were identified, the isolates should be assigned to the genus Endozoicomonas on the basis of congruity of phylogeny and should be classified as representatives of a novel species, for which the name Endozoicomonas numazuensis sp. nov. is proposed. The type strain is HC50(T) (â=âNBRC 108893(T) â=âDSM 25634(T)). An emended description of the genus Endozoicomonas is presented.
Asunto(s)
Gammaproteobacteria/clasificación , Filogenia , Poríferos/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , Gammaproteobacteria/genética , Gammaproteobacteria/aislamiento & purificación , Japón , Datos de Secuencia Molecular , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Two aerobic, Gram-reaction-negative, golden-yellow pigmented and rod-shaped bacteria, designated strains A5Q-118(T) and A5Q-27, were isolated from an unidentified sea squirt that thrives in the coral reefs off the coast of Okinawa, Japan. Phylogenetic analyses based on the 16S rRNA gene sequence revealed that the novel isolates were affiliated with the family 'Flammeovirgaceae' of the phylum Bacteroidetes. Strains A5Q-118(T) and A5Q-27 shared 100â% sequence similarity with each other and showed <92â% similarity with other cultivated members of the family 'Flammeovirgaceae'. The novel isolates were phenotypically and physiologically different from strains described previously. The DNA G+C content was 35.5-36.2 mol%, MK-7 was the major menaquinone and iso-C(15â:â0) and C(16â:â1)ω5c were the major fatty acids. Based on the results of this polyphasic taxonomic study, it was concluded that strains A5Q-118(T) and A5Q-27 represent a novel species in a new genus of the family 'Flammeovirgaceae', for which the name Aureibacter tunicatorum gen. nov., sp. nov. is proposed. Proposal for designation of the Flammeovirgaceae fam. nov. is also presented. The type strain of Aureibacter tunicatorum is A5Q-118(T) (â=âKCTC 23232(T) â=âNBRC 107587(T)).
Asunto(s)
Bacteroidetes/clasificación , Bacteroidetes/aislamiento & purificación , Urocordados/microbiología , Aerobiosis , Animales , Técnicas de Tipificación Bacteriana , Bacteroidetes/genética , Bacteroidetes/fisiología , Composición de Base , Análisis por Conglomerados , Arrecifes de Coral , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Japón , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Filogenia , Pigmentos Biológicos/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análisisRESUMEN
A gram-negative-staining, obligately aerobic, non-motile, rod-shaped and chemoheterotrophic bacterium, designated strain MN1-1006(T), was isolated from an ascidian (sea squirt) sample, and was studied using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the new isolate shared approximately 93-99% sequence similarity with recognized species of the genus Rubritalea within the phylum 'Verrucomicrobia'. DNA-DNA hybridization values between strain MN1-1006(T) and Rubritalea squalenifaciens HOact23(T) and Rubritalea sabuli YM29-052(T) were 57% and 14.5%, respectively. Strain MN1-1006(T) produced carotenoid compounds that rendered the cell biomass a reddish pink colour. The strain also contained squalene. The cell-wall peptidoglycan of the novel strain contained muramic acid and meso-diaminopimelic acid. The DNA G+C content of strain MN1-1006(T) was 51.4 mol%. The major cellular fatty acids were iso-C(14:0), iso-C(16:0) and anteiso-C(15:0). The major isoprenoid quinone was MK-9. On the basis of these data, it was concluded that strain MN1-1006(T) represents a novel species of the genus Rubritalea, for which the name Rubritalea halochordaticola sp. nov. is proposed. The type strain is MN1-1006(T )(â=âKCTC 23186(T)â=âNBRC 107102(T)).
Asunto(s)
Filogenia , Urocordados/microbiología , Verrucomicrobia/clasificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Carotenoides/química , Pared Celular/química , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Japón , Datos de Secuencia Molecular , Ácidos Murámicos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Verrucomicrobia/genética , Verrucomicrobia/aislamiento & purificación , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A new catechol-type siderophore, streptobactin (1), was isolated from a culture broth of the marine-derived actinomycete Streptomyces sp. YM5-799. The structure of streptobactin was determined by NMR and MS analyses and ESIMS/MS experiments to be a cyclic trimer of benarthin. A dibenarthin (2), a tribenarthin (3), and benarthin (4) were also obtained. The production of 1 was regulated by an iron concentration in the culture. The iron-chelating activity of the compounds was evaluated by the chrome azurol sulfonate assay.
Asunto(s)
Péptidos Cíclicos/aislamiento & purificación , Sideróforos/aislamiento & purificación , Dipéptidos/química , Dipéptidos/aislamiento & purificación , Biología Marina , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Péptidos Cíclicos/química , Sideróforos/química , Streptomyces/químicaRESUMEN
Ariakemicins A (1) and B (2), unusual linear hybrid polyketide-nonribosomal peptide antibiotics, were discovered from the fermentation extract of the marine gliding bacterium Rapidithrix sp. These metabolites were positional isomers with regard to a double bond and chromatographically inseparable, rendering the structure study on a mixture basis. The ariakemicins were composed of threonine, two omega-amino-(omega-3)-methyl carboxylic acids with diene or triene units, and delta-isovanilloylbutyric acid. The antibiotics selectively inhibited the growth of Gram-positive bacteria.
Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacteroidetes/química , Bacterias Grampositivas/efectos de los fármacos , Oligopéptidos/aislamiento & purificación , Oligopéptidos/farmacología , Polienos/aislamiento & purificación , Polienos/farmacología , Antibacterianos/química , Biología Marina , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oligopéptidos/química , Polienos/químicaRESUMEN
A novel alpha-pyrone designated as alcanivorone was found in a culture broth of the marine bacterium, Alcanivorax jadensis, and its structure was determined by an analysis of 1D NMR, 2D NMR and MS data. Alcanivorone was produced by A. jadensis only when sodium pyruvate was added to the culture medium as a carbon source. Incorporation experiments using stable isotope-labeled pyruvate indicated that alcanivorone was biosynthesized from four molecules of pyruvate.
Asunto(s)
Alcanivoraceae/metabolismo , Antiinfecciosos/metabolismo , Pironas/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pironas/aislamiento & purificación , Pironas/metabolismo , Pironas/farmacologíaRESUMEN
Two new antibiotic depsipeptides, unnarmicins C (1) and A (2), were isolated from the fermentation broth of a marine bacterium, Photobacterium sp. strain MBIC06485. The structure of 1 was established by spectroscopic studies and chiral analyses of its chemical degradation/conversion products, and that of 2 by comparing its NMR, MS, and CD data with those of 1. Both compounds selectively inhibited the growth of two strains belonging to the genus Pseudovibrio, one of the most prevalent genera in the marine environments within the class Alphaproteobacteria.
Asunto(s)
Antibacterianos/biosíntesis , Antibacterianos/química , Depsipéptidos/biosíntesis , Depsipéptidos/química , Photobacterium/metabolismo , Antibacterianos/farmacología , Depsipéptidos/farmacología , Fermentación , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Photobacterium/clasificación , EstereoisomerismoRESUMEN
Ascochytatin, a new spirodioxynaphthalene metabolite produced by a marine-derived fungus, was found from a screening program focused on the bacterial two-component regulatory system. The structure of ascochytatin was determined by spectroscopic methods, including NMR and MS. The relative stereochemistry was determined by an X-ray crystallographic analysis, and the absolute stereochemistry was determined by the modified Mosher's method.
Asunto(s)
Antibacterianos/farmacología , Ascomicetos/química , Naftalenos/farmacología , Compuestos de Espiro/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibióticos Antineoplásicos/aislamiento & purificación , Antibióticos Antineoplásicos/farmacología , Ascomicetos/clasificación , Bacillus subtilis/efectos de los fármacos , Bacterias/efectos de los fármacos , Línea Celular Tumoral , Fenómenos Químicos , Química Física , Cromatografía en Capa Delgada , Cristalografía por Rayos X , Medios de Cultivo , Humanos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Naftalenos/química , Naftalenos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Compuestos de Espiro/química , Compuestos de Espiro/aislamiento & purificaciónRESUMEN
A new sulfoalkylresorcinol (1) was isolated from the marine-derived fungus, Zygosporium sp. KNC52. The structure of 1 was elucidated by spectroscopic methods including MS and NMR, and the absolute stereochemistry was determined by the modified Mosher's method. Compound 1 inhibited FtsZ polymerization in vitro and exhibited weak antimicrobial activity against multi-drug-resistant bacteria.