RESUMEN
The bacterial strain SECRCQ15T was isolated from seeds of Chenopodium quinoa in Spain. Phylogenetic, chemotaxonomic, and phenotypic analyses, as well as genome similarity indices, support the classification of the strain into a novel species of the genus Ferdinandcohnia, for which we propose the name Ferdinandcohnia quinoae sp. nov. To dig deep into the speciation features of the strain SECRCQ15T, we performed a comparative genomic analysis of the genome of this strain and those of the type strains of species from the genus Ferdinandcohnia. We found several genes related with plant growth-promoting mechanisms within the SECRCQ15T genome. We also found that singletons of F. quinoae SECRCQ15T are mainly related to the use of carbohydrates, which is a common trait of plant-associated bacteria. To further reveal speciation events in this strain, we revealed genes undergoing diversifying selection (e.g., genes encoding ribosomal proteins) and functions likely lost due to pseudogenization. Also, we found that this novel species contains 138 plant-associated gene-cluster functions that are unique within the genus Ferdinandcohnia. These features may explain both the ecological and taxonomical differentiation of this new taxon.
Asunto(s)
Ácidos Grasos , Plantas , Filogenia , Plantas/genética , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Análisis de Secuencia de ADNRESUMEN
Strain CRRU44T was isolated from the stems of Rubus ulmifolius plants growing in Salamanca (Spain). The phylogenetic analysis of the 16S rRNA gene sequence places this strain within the family Rhizobiaceae showing that it is equidistant to the type species of several genera from this family with similarity values ranging from 91.0 to 96.3â%. Strain CRRU44T formed a divergent lineage which clustered with Endobacterium cereale RZME27T, Neorhizobium galegae HAMBI540T and Pseudorhizobium pelagicum R1-200B4T. The phylogenomic analysis showed that strain CRRU44T was equal to or more distant from the remaining genera of the family Rhizobiaceae than other genera among them. The calculated average nucleotide identity based on blast and average amino acid identity values with respect to the type species of all genera from the family Rhizobiaceae were lower than 78.5 and 76.5â%, respectively, which are the currently cut-off values proposed to differentiate genera within this family. All these results together with those from phenotypic and chemotaxonomic analyses support that strain CRRU44T represents a novel species of a novel genus within the family Rhizobiaceae, for which the name Ferranicluibacter rubi gen. nov., sp. nov. is proposed (type strain CRRU44T=CECT 30117T=LMG 31822T).
Asunto(s)
Rhizobiaceae , Rubus , Rubus/genética , Ácidos Grasos/química , Análisis de Secuencia de ADN , España , Filogenia , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Composición de BaseRESUMEN
Two novel Micromonospora strains, STR1-7T and STR1S-6T, were isolated from the rhizosphere of a Parastrephia quadrangularis plant growing in the Salar de Tara region of the Atacama Desert, Chile. Chemotaxonomic, cultural and phenotypic features confirmed that the isolates belonged to the genus Micromonospora. They grew from 20 to 37â°C, from pH7 to 8 and in the presence of up to 3â%, w/v NaCl. The isolates formed distinct branches in Micromonospora gene trees based on 16S rRNA gene sequences and on a multi-locus sequence analysis of conserved house-keeping genes. A phylogenomic tree generated from the draft genomes of the isolates and their closest phylogenetic neighbours showed that isolate STR1-7T is most closely related to Micromonospora orduensis S2509T, and isolate STR1S-6 T forms a distinct branch that is most closely related to 12 validly named Micromonospora species, including Micromonospora saelicesensis the earliest proposed member of the group. The isolates were separated from one another and from their closest phylogenomic neighbours using a combination of chemotaxonomic, genomic and phenotypic features, and by low average nucleotide index and digital DNA-DNA hybridization values. Consequently, it is proposed that isolates STR1-7T and STR1S-6T be recognized as representing new species in the genus Micromonospora, namely as Micromonospora parastrephiae sp. nov. and Micromonospora tarensis sp. nov.; the type strains are STR1-7T (=CECT 9665T=LMG 30768T) and STR1S-6T (=CECT 9666T=LMG 30770T), respectively. Genome mining showed that the isolates have the capacity to produce novel specialized metabolites, notably antibiotics and compounds that promote plant growth, as well as a broad-range of stress-related genes that provide an insight into how they cope with harsh abiotic conditions that prevail in high-altitude Atacama Desert soils.
Asunto(s)
Fabaceae , Micromonospora , Técnicas de Tipificación Bacteriana , Ácidos Grasos/química , Análisis de Secuencia de ADN , Chile , Filogenia , Rizosfera , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de BaseRESUMEN
Rear-edge populations at the xeric distribution limit of tree species are particularly vulnerable to forest dieback triggered by drought. This is the case of silver fir (Abies alba) forests located in Southwestern Europe. While silver fir drought-induced dieback patterns have been previously explored, information on the role played by nutritional impairment is lacking despite its potential interactions with tree carbon-water balances. We performed a comparative analysis of radial growth, intrinsic water-use efficiency (iWUE), oxygen isotopes (δ18 O) and nutrient concentrations in leaves of declining (DD) and non-declining (ND) trees in silver fir in four forests in the Spanish Pyrenees. We also evaluated the relationships among dieback predisposition, intraspecific trait variation (wood density and leaf traits) and rhizosphere soil physical-chemical properties. The onset of growth decline in DD trees occurred more than two decades ago, and they subsequently showed low growth resilience against droughts. The DD trees presented consistently lower foliar concentrations of nutrients such as P, K, Cu and Ni than ND trees. The strong effects of foliar nutrient status on growth resilience indices support the key role played by mineral nutrition in tree functioning and growth before, during and after drought. In contrast, variability in wood density and leaf morphological traits, as well as soil properties, showed weak relationships with tree nutritional status and drought performance. At the low elevation, warmer sites, DD trees showed stronger climate-growth relationships and lower δ18 O than ND trees. The uncoupling between iWUE and δ18 O, together with the positive correlations between P and K leaf concentrations and δ18 O, point to deeper soil/bedrock water sources and vertical decoupling between nutrient and water uptake in DD trees. This study provides novel insights into the mechanisms driving silver fir dieback and highlights the need to incorporate tree nutrition into forest dieback studies.
Las poblaciones del límite xérico de distribución de las especies de árboles son particularmente vulnerables al decaimiento forestal inducido por sequía. Este es el caso de los bosques de abeto (Abies alba) situados en el suroeste de Europa. Si bien los patrones de decaimiento provocado por sequía del abeto se han explorado previamente, falta información sobre el papel que desempeña el deterioro nutricional a pesar de sus interacciones potenciales con los balances de agua y carbono de los árboles. En este estudio, hemos realizado un análisis comparativo del crecimiento radial, la eficiencia intrínseca del uso del agua (iWUE), los isótopos de oxígeno (δ18O) y las concentraciones de nutrientes en hojas de árboles decaídos (DD) y no decaídos (ND) en cuatro abetares de los Pirineos españoles. También evaluamos las relaciones entre la predisposición al decaimiento, la variación de rasgos intraespecíficos (densidad de la madera y rasgos de las hojas) y las propiedades físico-químicas de la rizosfera. El inicio de la disminución del crecimiento en los árboles DD ocurrió hace más de dos décadas y posteriormente mostraron una baja resiliencia de crecimiento frente a las sequías. Los árboles DD presentaron concentraciones foliares consistentemente más bajas de nutrientes como P, K, Cu y Ni que los árboles ND. Los fuertes efectos del estado de los nutrientes foliares en los índices de resiliencia del crecimiento respaldan el papel clave que desempeña la nutrición mineral en el funcionamiento y el crecimiento de los árboles antes, durante y después de la sequía. En contraste, la variabilidad en la densidad de la madera y los rasgos morfológicos de las hojas, así como las propiedades del suelo, mostraron una relación débil con el estado nutricional de los árboles y la respuesta del crecimiento a la sequía. En los sitios más cálidos y de baja elevación, los árboles DD mostraron relaciones clima-crecimiento más fuertes y un δ18 O más bajo que los árboles ND. El desacoplamiento entre iWUE y δ18 O, junto con las correlaciones positivas entre las concentraciones foliares de P y K y δ18 O, apuntan a fuentes de agua más profundas del suelo/lecho rocoso y un desacoplamiento vertical entre la absorción de nutrientes y agua en los árboles DD. Este estudio proporciona información novedosa sobre los mecanismos que impulsan el decaimiento del abeto y destaca la necesidad de incorporar la nutrición de los árboles en los estudios de muerte regresiva del bosque.
Asunto(s)
Carbono , Sequías , Bosques , Suelo , Árboles , AguaRESUMEN
A new strain belonging to the genus Kocuria, designed PT10, was isolated from irradiated roots of the xerophyte Panicum turgidum. Isolate PT10 is a Gram-positive, coccoid, aerobic and ionizing-radiation (IR)-resistant actinobacterium. PT10 has shown an ability to survive under extreme conditions, such as gamma irradiation, desiccation and high concentration of hydrogen peroxide. Phenotypic, chemotaxonomic and comparative genome analyses support the assignment of strain PT10 (LMG 31102 = DSM 108617) as Kocuria rhizophila. The complete genome sequence of PT10 consists of one chromosome (2,656,287 bps), with a 70.7% G + C content and comprises 2481 protein-coding sequences. A total of 1487 proteins were identified by LC-MS/MS profiling. In silico analyses revealed that the proteome of the oxidation-tolerant PT10 possesses several features explaining its IR-resistant phenotype and many adaptive pathways implicated in response to environmental pressures - desiccation, cold, reactive oxygen species and other stressors.
Asunto(s)
Genes Bacterianos , Micrococcaceae/genética , Panicum/microbiología , Tolerancia a Radiación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Desecación , Rayos gamma , Micrococcaceae/patogenicidad , Micrococcaceae/efectos de la radiación , Estrés OxidativoRESUMEN
A novel strain of the genus Promicromonospora, designated PT9T, was recovered from irradiated roots of the xerophyte Panicum turgidum collected from the Ksar Ghilane oasis in southern Tunisia. Strain PT9T is aerobic, non-spore-forming, Gram- positive actinomycete that produces branched hyphae and forms white to yellowish-white colonies. Chemotaxonomic features, including fatty acids, whole cell sugars and polar lipid profiles, support the assignment of PT9T to the genus Promicromonospora. The genomic relatedness indexes based on DNA-DNA hybridization and average nucleotide identity values revealed a significant genomic divergence between strain PT9T and all sequenced type strains of the taxon. Phylogenomic analysis showed that isolate PT9T was most closely related to Promicromonospora soli CGMCC 4.7398T. Phenotypic and phylogenomic analyses suggest that isolate PT9T represents a novel species of the genus Promicromonospora, for which the name Promicromonospora panici sp. nov. is proposed. The type strain is PT9T (LMG 31103T = DSM 108613T).The isolate PT9T is an ionizing-radiation-resistant actinobacterium (D10 value = 2.6 kGy), with resistance to desiccation and hydrogen peroxide. The complete genome sequence of PT9T consists of 6,582,650 bps with 71.2% G+C content and 6291 protein-coding sequences. This genome will help to decipher the microbial genetic bases for ionizing-radiation resistance mechanisms including the response to oxidative stress.
Asunto(s)
Actinobacteria/clasificación , Panicum/microbiología , Filogenia , Radiación Ionizante , Actinobacteria/aislamiento & purificación , Actinobacteria/efectos de la radiación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Raíces de Plantas/microbiología , ARN Ribosómico 16S , Análisis de Secuencia de ADN , TúnezRESUMEN
The original type strains of Agrobacterium radiobacter and Agrobacterium tumefaciens recorded in the eighth edition of Bergey's Manual of Determinative Bacteriology published in 1974 were NCIB 9042T and ATCC 4720T, respectively. However, in the list of the valid names of bacteria compiled in 1980, both strains were changed, A. radiobacter NCIB 9042T to ATCC 19358T and A. tumefaciens ATCC 4720T to ATCC 23308T. These changes were unjustified, particularly in the case of A. tumefaciens whose type strain was replaced by another strain from the same collection, although the original type strain ATCC 4720T was never lost and it is currently available in several culture collections. Therefore, we request that the type strain of A. tumefaciens be corrected from ATCC 23308T to ATCC 4720T.
Asunto(s)
Agrobacterium tumefaciens/clasificación , Filogenia , Terminología como AsuntoRESUMEN
Three presumptive Modestobacter strains isolated from a high altitude Atacama Desert soil were the subject of a polyphasic study. The isolates, strains 1G4T, 1G51 and 1G52, were found to have chemotaxonomic and morphological properties that were consistent with their assignment to the genus Modestobacter. They formed a well supported clade in Modestobacter 16S rRNA gene trees and were most closely related to the type strain of 'Modestobacter excelsi' (99.8-99.9% similarity). They were also closely related to the type strains of Modestobacter caceresii (99.6â% similarity), Modestobacter italicus (99.7-99.9% similarity), Modestobacter lacusdianchii (98.4-99.2% similarity), Modestobacter marinus (99.4-99.5% similarity) and Modestobacter roseus (99.3-99.5% similarity), but were distinguished from their closest relatives by a combination of phenotypic features. Average nucleotide identity and digital DNA:DNA hybridization similarities drawn from comparisons of draft genome sequences of isolate 1G4T and its closest phylogenetic neighbours mentioned above, were well below the threshold used to assign closely related strains to the same species. The close relationship between isolate 1G4T and the type strain of M. excelsi was showed in a phylogenomic tree containing representative strains of family Geodermatophilaceae. The draft genome sequence of isolate 1G4T (size 5.18 Kb) was shown to be rich in stress related genes providing further evidence that the abundance of Modestobacter propagules in Atacama Desert habitats reflects their adaptation to the harsh environmental conditions prevalent in this biome. In light of all of these data it is proposed that the isolates be assigned to a novel species in the genus Modestobacter. The name proposed for this taxon is Modestobacter altitudinis sp. nov., with isolate 1G4T (=DSM 107534T=PCM 3003T) as the type strain.
Asunto(s)
Actinobacteria/clasificación , Clima Desértico , Filogenia , Microbiología del Suelo , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Chile , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Strain EAR18T was isolated as an endophyte from the roots of a halophyte plant, Arthrocnemum macrostachyum, growing in the Odiel marshes (Huelva, Spain). Cells of strain EAR18T were Gram- stain-negative, motile, non-spore-forming aerobic rods. It grew optimally on tryptic soy agar supplemented with 2.5â% NaCl (w/v), at pH 7 and 30 °C for 48 h. It tolerated NaCl from 0 to 25 % (w/v). It presented Q9 as the major quinone and C19â:â0 cyclo ω8c, summed feature 8 (C18â:â1ω7c and/or C18â:â1ω6c) and C16â:â0 as the predominant fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and four unidentified phospholipids. The results of phylogenetic analysis based on 16S rRNA gene sequences revealed that strain EAR18T formed a well-supported clade with species Halomonas zincidurans B6T and Halomonas xinjiangensis TRM 0175T (similarities of 98.3 and 96.1â% respectively). Furthermore, digital DNA-DNA hybridization analysis resulted in values of 20.4â% with H. xinjiangensis TRM 0175T and 35.50â% with H. zincidurans B6T, and ANIb/ANIm results in values of 73.8 %/84.2â% with H. xinjiangensis TRM 0175T and 86.8 %/89.4â% with H. zincidurans B6T. Based on phylogeny and differential phenotypic properties in comparison with its closest related species, strain EAR18T is suggested to represent a new species in the genus Halomonas, for which the name Halomonas radicis sp. nov. is proposed. The type strain is EAR18T (=CECT 9077T=LMG 29859T). The whole genome was sequenced, and it had a total length of 4.6 Mbp and a G+C content of 64.9 mol%.
Asunto(s)
Chenopodiaceae/microbiología , Halomonas/clasificación , Filogenia , Raíces de Plantas/microbiología , Humedales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Endófitos/clasificación , Endófitos/aislamiento & purificación , Ácidos Grasos/química , Halomonas/aislamiento & purificación , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Plantas Tolerantes a la Sal/microbiología , Análisis de Secuencia de ADN , EspañaRESUMEN
A novel actinobacterial strain, designated S2509T, was isolated from marine sediment collected by a dredge at a depth of 45 m along Melet River offshore of the southern Black Sea coast, Ordu, Turkey. The cell wall peptidoglycan of strain was found to contain meso-diaminopimelic acid and 3-OH-diaminopimelic acid. The whole cell sugars detected were arabinose, glucose, rhamnose, ribose and xylose. The diagnostic phospholipids of strain S2509T were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, a glycolipid and two unidentified phospholipids. The predominant menaquinones were identified as MK-9(H8), MK-9(H6), MK-10(H8), MK-9(H4), MK-10(H4) and MK-10(H6). The major cellular fatty acids were found to be iso-C16:0, iso-C15:0 and 10-methyl C17:0. The taxonomic position of the strain was established using a polyphasic approach, showing that S2509T strain belongs to the genus Micromonospora. Phylogenetic analysis based on the 16S rRNA gene sequence of strain S2509T showed that it is closely related to the type strain of Micromonospora chokoriensis DSM 45160T (99.37% sequence similarity), and phylogenetically clustered with Micromonospora inaquosa LB39T (99.37%), Micromonospora lupini Lupac 14NT (99.16%), Micromonospora violae NEAU-zh8T (99.23%) and Micromonospora taraxaci NEAU-P5T (99.03%). The phylogenetic analysis based on the gyrB gene sequence of strain S2509T confirmed its close relationship with M. chokoriensis JCM 13247T (96.5% sequence similarity). Whole genome sequences confirmed by digital DNA-DNA hybridization analysis that the strain S2509T represents a novel species in the genus Micromonospora, for which the name Micromonospora orduensis sp. nov. is proposed. The type strain is S2509T (=DSM 45926T = KCTC 29201T).
Asunto(s)
Organismos Acuáticos , Sedimentos Geológicos/microbiología , Micromonospora/clasificación , Micromonospora/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Ácidos Grasos/metabolismo , Genoma Bacteriano , Genómica/métodos , Micromonospora/genética , Filogenia , Agua de Mar/microbiología , Microbiología del SueloRESUMEN
A novel actinobacterial strain, designated NA12T, was isolated from coastal sediment sample of Nemrut Lake, a crater lake in eastern Anatolia, Turkey. The taxonomic position of the strain was established using a polyphasic approach. Cultural and chemotaxonomic characteristics of the strain were consistent with its classification within the family Micromonosporaceae. The 16S rRNA gene sequence analysis of strain NA12T showed that the strain closely related to M. radicis AZ1-13T, M. zingiberis PLAI 1-1T, M. craniella LHW63014T and M. endophytica 202201T with pairwise sequence identity values ranging from 99.4 to 99.3%. Digital DNA-DNA hybridization values between strain NA12T and the closely related type strains were ranged from 41.0 to 18.3% while the average nucleotide identity values were between 87.3 and 86.5%, which are well below the designed cut-off points of 70 and 95%, respectively. The G + C content of genomic DNA was 71.5%. Whole-cell hydrolysates of strain NA12T contained 3-hydroxydiaminopimelic acid and meso-diaminopimelic acid. Cell-wall sugars were composed of arabinose, fucose, glucose, mannose, rhamnose and xylose. The polar lipid profile contained phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, glycophospholipid, amino-phospholipid and two unidentified phospholipids. The predominant menaquinones were MK-9(H6) and MK-9(H4). Major fatty acids were iso-C16:0 and C17:1ω8c. Based upon the consensus of phenotypic and phylogenetic analyses as well as whole genome comparisons, strain NA12T (DSM 100982T = KCTC 39647T) is proposed to represent the type strain of a novel species, Micromonospora craterilacus sp. nov.
Asunto(s)
Micromonospora , Actinobacteria/clasificación , Pared Celular/química , ADN Bacteriano/genética , Ácidos Grasos/análisis , Lagos/microbiología , Micromonospora/clasificación , Micromonospora/genética , Micromonospora/aislamiento & purificación , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , TurquíaRESUMEN
A novel actinobacterial strain, designated GTF31T, was isolated from a coastal soil sample of Gölcük Lake, a crater lake in southwest Anatolia, Turkey. The taxonomic position of the strain was established using a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences and showed that the strain is closely related to Jiangella gansuensis DSM 44835T (99.4%), Jiangella alba DSM 45237T (99.3%) and Jiangella muralis DSM 45357T (99.2%). Optimal growth was observed at 28 °C and pH 7-8. Whole cell hydrolysates were found to contain LL-DAP, glucose, mannose, rhamnose and ribose. The predominant menaquinone was identified as MK-9(H4). The polar lipid profile was found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, glycophospholipids and unidentified phospholipids. The major fatty acids were identified as anteiso-C15:0, iso-C16:0 and anteiso-C17:0. The G + C content of the type strain was determined to be 72.5% and the size of the draft genome is 7.0 Mb. The calculated digital DDH values between strain GTF31T and the type strains of J. gansuensis, J. alba, J. muralis and Jiangella alkaliphila ranged from 24.4 to 34.4% and ANI values ranged between 81.0 and 87.9%. Based upon the consensus of phenotypic and phylogenetic analyses as well as whole genome comparisons, strain GTF31T (= DSM 100984T = CECT 9378T) is proposed to represent the type strain of a novel species, Jiangella anatolica sp. nov.
Asunto(s)
Actinobacteria/aislamiento & purificación , Sedimentos Geológicos/microbiología , Lagos/microbiología , Actinobacteria/clasificación , Actinobacteria/genética , Actinobacteria/metabolismo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Ribosómico/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Filogenia , ARN Ribosómico 16S/genética , TurquíaRESUMEN
A Gram-negative rod, designated strain LLAN61T, was isolated from a root nodule of Lotus lancerottensis growing in a saline soil sample from Lanzarote (Canary Islands). The strain grew optimally at 0.5â% (w/v) NaCl and tolerated up to 3.5â%. The 16S rRNA gene sequence analysis showed that strain LLAN61T belonged to genus Phyllobacterium and that Phyllobacteriumleguminum ORS 1419T and Phyllobacteriummyrsinacearum IAM 13584T are the closest related species with 97.93 and 97.86% similarity values, respectively. In the atpD phylogeny, P. leguminum ORS 1419T and P. myrsinacearum ATCC 43591T, sharing similarities of 87.6 and 85.8% respectively, were also the closest species to strain LLAN61T. DNA-DNA hybridization showed an average value of 21â% between strain LLAN61T and P. leguminum LMG 22833T, and 6â% with P. myrsinacearum ATCC 43590T. The predominant fatty acids were C19â:â0 cyclo ω8c and C18â:â1ω6c/C18â:â1ω7c (summed feature 8). The DNA G+C content was 58.0 mol%. Strain LLAN61T differed from its closest relatives in some culture conditions and in assimilation of several carbon sources. Based upon the results of phylogeny, DNA-DNA hybridization, phenotypic tests and fatty acid analysis, this strain should be classified as a novel species of Phyllobacterium for which the name Phyllobacterium salinisoli sp. nov. is proposed (type strain LLAN61T=LMG 30173T = CECT 9417T).
Asunto(s)
Lotus/microbiología , Phyllobacteriaceae/clasificación , Filogenia , Raíces de Plantas/microbiología , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Phyllobacteriaceae/genética , Phyllobacteriaceae/aislamiento & purificación , ARN Ribosómico 16S/genética , Salinidad , Análisis de Secuencia de ADN , EspañaRESUMEN
A bacterial strain designated CRZM18RT was isolated from a root of Zea mays in Spain. The analysis of the 16S rRNA gene sequence showed that this strain belongs to the genus Rhizobium, with Rhizobium cellulosilyticum ALA10B2T and Rhizobium yantingense H66T being the most closely related species with 98.3 and 97.9â% sequence similarity, respectively. The analysis of the concatenated recA and atpD genes showed that strain CRZM18RT forms a cluster with these species and also with Rhizobiumsmilacinae PTYR-5T, but the recA and atpD genes of strain CRZM18RT were phylogenetically distant, with identities lower than 90 and 96â%, respectively. DNA-DNA hybridization analysis showed mean relatedness of 43, 22 and 38â% with respect to R. cellulosilyticum ALA10B2T, R. yantingense LMG 28229T and R. smilacinae LMG 27604T. Phenotypic characteristics also differed from those of the most closely related species of the genus Rhizobium. The major fatty acids were those from summed feature 8 (C18â:â1ω6c/C18â:â1ω7c) and C16â:â0. Based on the genotypic, chemotaxonomic and phenotypic data obtained in this study, we propose to classify strain CRZM18RT in a novel species named Rhizobium zeae sp. nov. (type strain CRZM18RT=LMG 29735T=CECT 9169T).
Asunto(s)
Filogenia , Raíces de Plantas/microbiología , Rhizobium/clasificación , Zea mays/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Rhizobium/genética , Rhizobium/aislamiento & purificación , Análisis de Secuencia de ADN , EspañaRESUMEN
Eleven actinobacterial strains were isolated from a rock sample collected in the Atacama Desert. Molecular typing by BOX-PCR divided the strains into three clusters and showed that, although very similar, they were not clones. Three strains, ATK01, ATK03T and ATK17, each representing one of the defined BOX clusters, were chosen for further characterization. Phylogenetic analysis indicated that the strains were related to the genus Pseudonocardia and were recovered in a cluster together with Pseudonocardia bannensis YIM 63101T and Pseudonocardia xinjiangensis AS 4.1538T. Chemotaxonomic analyses confirmed their affiliation to the genus Pseudonocardia but differences were found between the new strains and their closest phylogenetic relatives. Physiological and fatty acid analyses also revealed differences between these strains and their phylogenetic neighbours supporting their status as a distinct species. Based on the overall data, it is proposed that strains ATK01, ATK03T and ATK17 represent a novel species of the genus Pseudonocardia for which the name Pseudonocardia nigra sp. nov. is proposed (type strain ATK03T=DSM 104088T=CECT 9183T).
Asunto(s)
Actinomycetales/clasificación , Clima Desértico , Filogenia , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Chile , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Two slow-growing strains, AMBPC1010T and AMBPC1011, were isolated from nodules of Cajanus cajan in the Dominican Republic. 16S rRNA gene analysis placed these strains within the genus Bradyrhizobium, being phylogenetically equidistant to several species of this genus. Analysis of the recA and atpD genes showed that the strains isolated belong to a cluster containing the strains Bradyrhizobium ottawaense OO99T, 'Bradyrhizobium americanum' CMVU44 and Bradyrhizobium daqingense CCBAU 15774T, and presented similarity values lower than 96â% for both genes with respect to the strains nodulating C. cajan. DNA-DNA hybridization analysis showed averages of 36, 40 and 39â% relatedness with respect to the representative strains of Bradyrhizobium ottawaense, 'Bradyrhizobium americanum' and Bradyrhizobium daqingense, respectively. Phenotypic characteristics also differed from those of the most closely related species of the genus Bradyrhizobium. Therefore, based on the data obtained in this study, we propose to classify the strains AMBPC1010T (=LMG 29967T=CECT 9227T) and AMBPC1011 into a novel species named Bradyrhizobium cajani sp. nov.
Asunto(s)
Bradyrhizobium/clasificación , Cajanus/microbiología , Filogenia , Nódulos de las Raíces de las Plantas/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Bradyrhizobium/genética , Bradyrhizobium/aislamiento & purificación , ADN Bacteriano/genética , República Dominicana , Genes Bacterianos , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , SimbiosisRESUMEN
A polyphasic study was undertaken to establish the taxonomic position of a non-chromogenic, rapidly growing Mycobacterium strain that had been isolated from sputum. The strain, CECT 8775T, has chemotaxonomic and cultural properties consistent with its classification in the genus Mycobacterium and was distinguished from the type strains of closely related mycobacterial species, notably from Mycobacterium paraense DSM 46749T, its nearest phylogenetic neighbour, based on 16S rRNA, hsp65 and rpoB gene sequence data. These organisms were also distinguished by a broad range of chemotaxonomic and phenotypic features and by a digital DNA-DNA relatedness value of 22.8â%. Consequently, the strain is considered to represent a novel species of Mycobacterium for which the name Mycobacterium eburneum sp. nov is proposed; the type strain is X82T (CECT 8775T=DSM 44358T).
Asunto(s)
Mycobacterium/clasificación , Filogenia , Esputo/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Humanos , Mycobacterium/genética , Mycobacterium/aislamiento & purificación , Infecciones por Mycobacterium/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , SuizaRESUMEN
A polyphasic study was undertaken to establish the taxonomic status of an Actinomadura strain isolated from the margin of a saline, alkaline lake in Central Anatolia, Turkey. Strain D310ATT was shown to have chemotaxonomic, cultural and morphological properties consistent with its classification in the genus Actinomadura such as hooked or irregular spiral spore chains, meso-diaminopimelic acid as the major cell wall diaminopimelic acid, and diphosphatidylglycerol and phosphatidylinositol as major polar lipids. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain D310ATT is closely, albeit loosely, associated with Actinomadura darangshiensis DLS-70T with 97.2% sequence similarity, but was readily separated from the latter using diverse phenotypic properties. Consequently, the isolate is considered to represent a new species of Actinomadura for which the name Actinomadura alkaliterrae sp. nov. is proposed, with the type strain D310ATT (=DSM 101185T = KCTC 39657T).
Asunto(s)
Actinomycetaceae/metabolismo , Filogenia , Microbiología del Suelo , Actinomycetaceae/aislamiento & purificación , Técnicas de Tipificación Bacteriana , ADN Bacteriano , Ácido Diaminopimélico/metabolismo , Ácidos Grasos , Hibridación de Ácido Nucleico , Fosfolípidos , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Suelo , TurquíaRESUMEN
A bacterial strain named IB1.1T was isolated in a screening of hydrocarbon-degrading bacteria from oil-contaminated soils on the territory of the Turukhansk District of Krasnoyarsk Krai, East Siberia, Russia. The 16S rRNA gene sequence had 98.7 % identity with respect to the closest phylogenetic relative, Pseudomonas granadensis F-278,770T, and the next most closely related species with 98.6 % similarity was Pseudomonaspunonensis, suggesting that IB1.1T should be classified within the genus Pseudomonas. The analysis of housekeeping genes rpoB, rpoD and gyrB showed similarities lower than 90 % in all cases with respect to the closest relatives, confirming its phylogenetic affiliation. The strain showed a polar flagellum. The respiratory quinone was Q9. The major fatty acids were 16 : 1ω7c/16 : 1ω6c (summed feature 3), 18 : 1ω7c and 16 : 0. The strain was oxidase- and catalase-positive, but the arginine dihydrolase system was not present. Nitrate reduction, urease and ß-galactosidase production, and aesculin hydrolysis were negative. The temperature range for growth was 4-34 °C, and the strain could grow at pH 11. The DNA G+C content was 58.5 mol%. DNA-DNA hybridization results showed values of less than 30 % relatedness with respect to the type strains of the eight most closely related species. Therefore, the dataset of genotypic, phenotypic and chemotaxonomic data support the classification of strain IB1.1T into a novel species of the genus Pseudomonas, for which the name Pseudomonasturukhanskensis sp. nov. is proposed. The type strain is IB1.1T (=VKM B-2935T=CECT 9091T).
Asunto(s)
Contaminación por Petróleo , Filogenia , Pseudomonas/clasificación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Pseudomonas/genética , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Federación de Rusia , Análisis de Secuencia de ADN , Siberia , Ubiquinona/químicaRESUMEN
In this work we revise the taxonomic status of the Lotus-nodulating strains MAFF 303099T and R7A isolated in Japan and New Zealand, respectively. Their 16S rRNA gene sequences are identical and show 98.0, 99.7, 99.8 and 99.9 % similarity values with respect to Mesorhizobium loti NZP 2213T, M. jarvisii ATCC 33669T, M. huakuii USDA 4779T (=CCBAU 2609T) and M. erdmanii USDA 3471T, respectively. The analysis of recA and glnII gene sequeces showed that M. jarvisii ATCC 33669T and M. huakuii USDA 4779T (=CCBAU 2609T) are the most closely related strains to MAFF 303099T and R7A, with similarity values suggesting that these two strains belong to a different species for which MAFF 303099T is selected as the type strain. The DNA-DNA relatedness values between strain MAFF 303099T and its closest phylogenetic relatives ranged from 53 to 60 % in average. Strains MAFF 303099T and R7A presented slight differences in the proportions of C18 : 1ω7c 11-methyl and C19 : 0 cyclo ω8c fatty acids with respect to M. jarvisii ATCC 33669T and M. huakuii USDA 4779T, and also in several phenotypic characteristics. Therefore, we propose the reclassification of these two strains into a novel species named Mesorhizobium japonicum sp. nov., with the type strain being MAFF 303099T (=LMG 29417T=CECT 9101T).