RESUMEN
Planctomycetes of the family Gemmataceae are characterized by large genome sizes and cosmopolitan distribution in freshwater and terrestrial environments but their ecological functions remain poorly understood. In this study, we characterized a novel representative of this family, strain PL17T, which was isolated from a littoral tundra wetland and was capable of growth on xylan and cellulose. Cells of this isolate were represented by pink-pigmented spheres that multiplied by budding and occurred singly or in short chains and aggregates. Strain PL17T was obligately aerobic, mildly acidophilic chemoorganotrophic bacterium, which displayed good tolerance of low temperatures. The major fatty acids were C18:0, C16:1ω5, and ßOH-C16:1; the major polar lipid was trimethylornithine. The genome of strain PL17T consisted of a 9.83 Mb chromosome and a 24.69kb plasmid. The G+C contents of the chromosomal and plasmid DNA were 67.4 and 62.3mol%, respectively. Over 8900 potential protein-coding genes were identified in the genome including a putative cellulase that contains a domain from the GH5 family of glycoside hydrolases. The genome of strain PL17T contained one linked and one unlinked rRNA operons with 16S rRNA gene sequences displaying 94.5% similarity to that in Gemmata obscuriglobus UQM2246T. Based on the results of comparative phenotypic, chemotaxonomic and phylogenomic analyses, we propose to classify strain PL17T (= CECT 9407T=VKM B-3467T) as representing a novel genus and species of the family Gemmataceae, Frigoriglobus tundricola gen. nov., sp. nov.
Asunto(s)
Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Tundra , Humedales , Bacterias , Técnicas de Tipificación Bacteriana , Composición de Base , Celulosa/metabolismo , Frío , ADN Bacteriano/química , ADN Bacteriano/genética , Ácidos Grasos/análisis , Genes Bacterianos , Genes de ARNr , Genoma Bacteriano , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/fisiología , Lípidos/análisis , Redes y Vías Metabólicas/genética , Filogenia , Planctomycetales/clasificación , Planctomycetales/genética , ARN Ribosómico 16S/genética , Xilanos/metabolismoRESUMEN
Biological nitrogen fixation plays an important role in nitrogen cycling by transferring atmospheric N2 to plant-available N in the soil. However, the diazotrophic activity and distribution in different types of soils remain to be further explored. In this study, 152 upland soils were sampled to examine the diazotrophic abundance, nitrogenase activity, diversity and community composition by quantitative polymerase chain reaction, acetylene reduction assay and the MiSeq sequencing of nifH genes, respectively. The results showed that diazotrophic abundance and nitrogenase activity varied among the three soil types. The diazotrophic community was mainly dominated by Bradyrhizobium, Azospirillum, Myxobacter, Desulfovibrio and Methylobacterium. The symbiotic diazotroph Bradyrhizobium was widely distributed among soils, while the distribution of free-living diazotrophs showed large variation and was greatly affected by multiple factors. Crop type and soil properties directly affected the diazotrophic É-diversity, while soil properties, climatic factors and spatial distance together influenced the diazotrophic community. Network structures were completely different among all three types of soils, with most complex interactions observed in the Red soil. These findings suggest that diazotrophs have various activities and distributions in the three soil types, which played different roles in nitrogen input in agricultural soil in China, being driven by multiple environmental factors.
Asunto(s)
Bacterias Aerobias Gramnegativas/metabolismo , Bacterias Anaerobias Gramnegativas/metabolismo , Fijación del Nitrógeno/fisiología , Oxidorreductasas/genética , Microbiología del Suelo , Agricultura , Bradyrhizobium , China , Granjas , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/genética , Bacterias Anaerobias Gramnegativas/clasificación , Bacterias Anaerobias Gramnegativas/genética , Nitrógeno/análisis , Suelo/química , SimbiosisRESUMEN
A Gram-stain negative, aerobic, rod-shaped, non-motile, yellow-pigmented and non-spore-forming bacterial strain, designated PM5-8T, was isolated from a culture of a marine toxigenic dinoflagellate Prorocentrum mexicanum PM01. Strain PM5-8T grew at 15-35 °C (optimum, 25-30 °C) and pH 6-11 (optimum, 7.5-8). Cells required at least 1.5% (w/v) NaCl for growth, and can tolerate up to 7.0% with the optimum of 4%. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the strain PM5-8T is closely related to members of the genus Hoeflea, with high sequence similarities with Hoeflea halophila JG120-1T (97.06%) and Hoeflea alexandrii AM1V30T (97.01%). DNA-DNA hybridization values between the isolate and other type strains of recognized species of the genus Hoeflea were between 11.8 and 25.2%, which is far below the value of 70% threshold for species delineation. The DNA G + C content was 50.3 mol%. The predominant cellular fatty acids of the strain were identified as summed feature 8 (C16:1 ω7c and/or C16:1 ω6c; 51.5%), C18:1 ω7c 11-methyl (20.7%), C16:0 (17.2%) and C18:0 (5.7%). The major respiratory quinone was Q-10. Polar lipids profiles contained phosphatidylcholine, phosphatidylglycerol, sulfoquinovosyl diacylglycerol, phosphatidylmono- methylethanolamine, phosphatidylethanolamine and four unidentified lipids. On the basis of the polyphasic taxonomic data presented, strain PM5-8T (= CCTCC AB 2016294T = KCTC 62490T) represents a novel species of the genus Hoeflea, for which the name Hoeflea prorocentri sp. nov. is proposed.
Asunto(s)
Organismos Acuáticos/microbiología , Dinoflagelados/microbiología , Bacterias Aerobias Gramnegativas/clasificación , ADN Bacteriano , Bacterias Aerobias Gramnegativas/química , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Metabolómica/métodos , Tipificación Molecular , Fenotipo , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
Achromatium is the largest freshwater bacterium known to date and easily recognised by conspicuous calcite bodies filling the cell volume. Members of this genus are highly abundant in diverse aquatic sediments and may account for up to 90% of the bacterial biovolume in the oxic-anoxic interfaces. The high abundance implies that Achromatium is either rapidly growing or hardly prone to predation. As Achromatium is still uncultivated and does not appear to grow fast, one could assume that the cells might escape predation by their unusual shape and composition. However, we observed various members of the meiofauna grazing or parasitizing on Achromatium. By microphotography, we documented amoebae, ciliates, oligochetes and plathelminthes having Achromatium cells ingested. Some Achromatium cells harboured structures resembling sporangia of parasitic fungi (chytrids) that could be stained with the chitin-specific dye Calcofluor White. Many Achromatia carried prokaryotic epibionts in the slime layer surrounding the cells. Their regular distribution over the cell might indicate that they are commensalistic rather than harming their hosts. In conclusion, we report on various interactions of Achromatium with the sediment community and show that although Achromatium cells are a crispy diet, full of calcite bodies, predators do not spare them.
Asunto(s)
Sedimentos Geológicos/microbiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Lagos/microbiología , Amoeba/fisiología , Animales , Cilióforos/fisiología , Sedimentos Geológicos/parasitología , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Lagos/parasitología , Oligoquetos/fisiologíaRESUMEN
Resumen Introducción: La sepsis neonatal nosocomial (SNN) es una entidad frecuente en las unidades de cuidados intensivos, donde causa una gran morbimortalidad. La ubicación más frecuente es bacteriemia, seguido de neumonía asociada a ventilador mecánico y vía urinaria. Objetivo: Conocer la etiología y localización más frecuente de la infección en el SNN. Población, Material y Métodos: Estudio retrospectivo, de prevalencias de enero a diciembre de 2015, realizado en la Unidad de Cuidados Intensivos Neonatal de un hospital de alta complejidad. Fueron incluidos todos los neonatos. Resultados: Se incluyeron 70 pacientes, se analizaron 88 episodios de SNN. La localización más frecuente fue sangre 40% de los casos, seguido de orina y aspirado traqueal en 25% respectivamente. Los microorganismos más frecuentemente aislados fueron Staphylococcus de diferentes tipos, seguido de Acinetobacter baumannii multi-resistente. La afectación del SNC fue de 32%. La mortalidad fue de 34%, elevándose a 50% ante un segundo episodio de SNN. La terapia empírica de elección fue vancomicina y carbapenem, ajustándose a antibiograma. Conclusiones: La infección más frecuente fue la bacteremia, principalmente por Staphylococcus resistentes a meticilina. La afectación del SNC fue elevada, lo mismo que la mortalidad.
Introduction: Nosocomial neonatal sepsis (NNS) is a frequent entity in intensive care units, causing great morbidity and mortality. The most frequent site is blood, followed by lungs and urine. Objective: To know the etiology and most frequent localization of infection in the NNS. Population, Material and Methods: Cross sectional study, from January to December 2015, performed in a teaching hospital. All newborns infants were included. Results: 70 patients were included, 88 episodes of NNS were analyzed. The most frequent localization was bacteremia in 40% of cases, followed by urinary tract infection and VAP in 25% respectively. The bacteria most frequently isolated were staphylococci of different types, followed by multiresistant Acinetobacter. The CNS involvement was 32%. Mortality was 34%, rising up to 50% with a second episode of NNS. The empirical therapy of choice was vancomycin and carbapenem, adjusting to antibiogram. Conclusions: The most frequent infection was bacteremia, mainly by staphylococci resistant to methicillin. CNS involvement was elevated, as well as mortality.
Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Infección Hospitalaria/microbiología , Sepsis Neonatal/microbiología , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Unidades de Cuidado Intensivo Neonatal , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Edad Gestacional , Bacteriemia/microbiología , Neumonía Asociada al Ventilador/microbiología , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/farmacologíaRESUMEN
In the aerobic methanotrophic bacteria Methylomicrobium alcaliphilum 20Z, Methylococcus capsulatus Bath, and Methylosinus trichosporium OB3b, the biochemical properties of hydroxypyruvate reductase (Hpr), an indicator enzyme of the serine pathway for assimilation of reduced C1-compounds, were comparatively analyzed. The recombinant Hpr obtained by cloning and heterologous expression of the hpr gene in Escherichia coli catalyzed NAD(P)H-dependent reduction of hydroxypyruvate or glyoxylate, but did not catalyze the reverse reactions of D-glycerate or glycolate oxidation. The absence of the glycerate dehydrogenase activity in the methanotrophic Hpr confirmed a key role of the enzyme in utilization of C1-compounds via the serine cycle. The enzyme from Ms. trichosporium OB3b realizing the serine cycle as a sole assimilation pathway had much higher special activity and affinity in comparison to Hpr from Mm. alcaliphilum 20Z and Mc. capsulatus Bath assimilating carbon predominantly via the ribulose monophosphate (RuMP) cycle. The hpr gene was found as part of gene clusters coding the serine cycle enzymes in all sequenced methanotrophic genomes except the representatives of the Verrucomicrobia phylum. Phylogenetic analyses revealed two types of Hpr: (i) Hpr of methanotrophs belonging to the Gammaproteobacteria class, which use the serine cycle along with the RuMP cycle, as well as of non-methylotrophic bacteria belonging to the Alphaproteobacteria class; (ii) Hpr of methylotrophs from Alpha- and Betaproteobacteria classes that use only the serine cycle and of non-methylotrophic representatives of Betaproteobacteria. The putative role and origin of hydroxypyruvate reductase in methanotrophs are discussed.
Asunto(s)
Hidroxipiruvato Reductasa/clasificación , Methylococcaceae/enzimología , Methylosinus/enzimología , Filogenia , Alphaproteobacteria , Gammaproteobacteria , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/enzimología , Hidroxipiruvato Reductasa/metabolismo , Methylobacillus , Methylobacteriaceae , Methylophilaceae , Serina/metabolismoRESUMEN
Two closely related aerobic, Gram reaction-negative rod-shaped bacteria (S7-75T and S7-80) were isolated from mucus of coral Fungia seychellensis from Andaman Sea, India. Heterotrophic growth on marine agar was observed at 4-35 °C and pH 6.5-10.5; optimum growth occurred at 25-30 °C and pH 7-8. 16 S rRNA sequence analysis confirmed the strains belonged to the genus Sulfitobacter and the two isolates shared more than 99.28% pairwise sequence similarity. DNA-DNA similarity between two isolates S7-75T and S7-80 was above 96%. Strain S7-75T showed maximum 16S rRNA similarity of 99.64% with Sulfitobacter pontiacus LMG 19752T. However, DNA-DNA relatedness between strain S7-75T and S. pontiacus LMG 19752T confirmed the placement of strain S7-75T as subspecies under the species S. pontiacus. Further, pulsed-field gel electrophoresis (PFGE), REP-PCR, ERIC-PCR fingerprint patterns and lipid profiles also differentiated strain S7-75T from the reference strain of S. pontiacus LMG 19752T. The DNA G+C content was 59.8 mol%. Q10 was the major respiratory quinone. Based on polyphasic analysis, the isolate S7-75T represents a subspecies of S. pontiacus for which the name S. pontiacus subsp. fungiae subsp. nov. is proposed with S7-75T (=JCM 31094T = LMG 29158T) as type strain.
Asunto(s)
Antozoos/microbiología , Bacterias Aerobias Gramnegativas/genética , Animales , Composición de Base/genética , ADN Bacteriano/genética , ADN Ribosómico/genética , Bacterias Aerobias Gramnegativas/clasificación , Rhodobacteraceae/clasificación , Rhodobacteraceae/genéticaRESUMEN
Advantages of MALDI-TOF MS (MS) were evaluated for diagnosis of bone and joint infections after enrichment of synovial fluid (SF) or crushed osteoarticular samples (CSs). MS was performed after enrichment of SF or crushed osteoarticular samples CS (n = 108) in both aerobic and anaerobic vials. Extraction was performed on 113 vials (SF: n = 47; CS: n = 66), using the Sepsityper® kit prior identification by MS. The performances of MS, score and reproducibility results on bacterial colonies from blood agar and on pellets after enrichment in vials, were compared. MS analysis of the vial resulted in correct identification of bacteria at a species and genus level (80.5% and 92% of cases, respectively). The reproducibility was superior for aerobic Gram-positive bacteria (Staphylococci and Gram-positive bacilli: 100% colonies), as compared to aerobic Gram-negative bacilli (89.7%), anaerobes (83.3%) and Streptococcus/Enterococcus (58.8%). MS performance was significantly better for staphylococci than for streptococci on all identification parameters. For polymicrobial cultures, identification (score>1.5) of two species by MS was acceptable in 92.8% of cases. Use of MS on enrichment pellets of bone samples is an accurate, rapid and robust method for bacterial identification of clinical isolates from osteoarticular infections, except for streptococci, whose identification to species level remains difficult.
Asunto(s)
Infecciones Bacterianas/diagnóstico , Enfermedades Óseas Infecciosas/diagnóstico , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Artropatías/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Líquido Sinovial/microbiología , Infecciones Bacterianas/microbiología , Técnicas Bacteriológicas , Enfermedades Óseas Infecciosas/microbiología , Huesos/microbiología , Huesos/fisiopatología , Coinfección/diagnóstico , Coinfección/microbiología , Medios de Cultivo/química , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Anaerobias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/microbiología , Bacterias Grampositivas/clasificación , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Artropatías/microbiología , Articulaciones/microbiología , Articulaciones/fisiopatología , Reproducibilidad de los Resultados , Staphylococcus/aislamiento & purificación , Streptococcus/aislamiento & purificaciónRESUMEN
BACKGROUND: Chestnut is a relatively new cultivated crop for Michigan, and postharvest loss due to decay has been problematic as production has increased each year. In 2007, more than 25% of chestnuts were lost to postharvest decay, equivalent to approximately 5300 kg of fresh product. To determine the organisms responsible for decay, a microbiological survey was performed in 2006 and 2007 to identify microorganisms involved in postharvest shell (external surface) mold and internal kernel (edible portion) decay of chestnuts. RESULTS: Filamentous fungi including Penicillium expansum, Penicillium griseofulvum, Penicillium chrysogenum, Coniophora puteana, Acrospeira mirabilis, Botryosphaeria ribis, Sclerotinia sclerotiorum, Botryotinia fuckeliana (anamorph Botrytis cinerea) and Gibberella sp. (anamorph Fusarium sp.) were the predominant microorganisms that negatively impacted fresh chestnuts. Populations of microorganisms varied between farms, harvesting methods and chestnut parts. CONCLUSION: Chestnuts harvested from the orchard floor were significantly (P < 0.05) more contaminated than chestnuts harvested directly from the tree, by more than 2 log colony-forming units (CFU) g(-1) . In addition, a significant difference (P < 0.05) in the microbial population was seen between chestnuts submitted by different growers, with average count ranges of fungi, mesophilic aerobic bacteria (MAB) and yeasts equal to 4.75, 4.59 and 4.75 log CFU g(-1) respectively. © 2016 Society of Chemical Industry.
Asunto(s)
Producción de Cultivos , Productos Agrícolas/microbiología , Fagaceae/microbiología , Inspección de Alimentos , Almacenamiento de Alimentos , Hongos/crecimiento & desarrollo , Nueces/microbiología , Ascomicetos/clasificación , Ascomicetos/crecimiento & desarrollo , Ascomicetos/aislamiento & purificación , Basidiomycota/clasificación , Basidiomycota/crecimiento & desarrollo , Basidiomycota/aislamiento & purificación , Botrytis/clasificación , Botrytis/crecimiento & desarrollo , Botrytis/aislamiento & purificación , Productos Agrícolas/crecimiento & desarrollo , Cruzamientos Genéticos , Fagaceae/crecimiento & desarrollo , Hongos/clasificación , Hongos/aislamiento & purificación , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Michigan , Tipificación Molecular , Técnicas de Tipificación Micológica , Nueces/crecimiento & desarrollo , Penicillium/clasificación , Penicillium/crecimiento & desarrollo , Penicillium/aislamiento & purificación , Phaeophyceae/clasificación , Phaeophyceae/crecimiento & desarrollo , Phaeophyceae/aislamiento & purificación , Microbiología del Suelo , Análisis Espacio-Temporal , Propiedades de Superficie , Levaduras/clasificación , Levaduras/crecimiento & desarrollo , Levaduras/aislamiento & purificaciónRESUMEN
A Gram-negative bacterium, denoted JLT2012(T), was isolated from the surface water of the Pacific Ocean. This aerobic bacterium was rod shaped and devoid of flagella, displayed gliding motility, and grew in characteristic orange colonies. The bacterium contained ubiquinone Q-10 as the major respiratory quinone, and spermidine and spermine as the major polyamine compounds. The dominant fatty acids were C18:1ω7c and/or C18:1ω6c (34.7 %), C16:0 (21.3 %), and C18:0 (15.9 %), whereas the polar lipids consisted mainly of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four sphingoglycolipids, and several unknown glycolipids. The G + C content DNA was found to be 65.5 mol%. Comparative 16S rRNA gene sequence analysis revealed that strain JLT2012(T) formed a distinct lineage within the genus Pacificimonas (formerly known as Pacificamonas) and shared the highest sequence similarity with the type strain of Pacificimonas flava JLT2015(T) (96.0 %). Data combined from different studies on the phenotypic, phylogenetic, and genomic characteristics indicated that strain JLT2012(T) is a representative of a novel species within Pacificimonas for which the name Pacificimonas aurantium sp. nov. (type strain JLT2012(T)=LMG 27361(T)=CGMCC 1.12399(T)) is proposed.
Asunto(s)
Bacterias Aerobias Gramnegativas/aislamiento & purificación , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/metabolismo , Océano Pacífico , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
The prompt and accurate identification of bacterial pathogens is fundamental to patient health and outcome. Recent advances in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) have revolutionized bacterial identification in the clinical laboratory, but uniform incorporation of this technology in the U.S. market has been delayed by a lack of FDA-cleared systems. In this study, we conducted a multicenter evaluation of the MALDI Biotyper CA (MBT-CA) System (Bruker Daltonics Inc, Billerica, MA) for the identification of aerobic gram-negative bacteria as part of a 510(k) submission to the FDA. A total of 2,263 aerobic gram negative bacterial isolates were tested representing 23 genera and 61 species. Isolates were collected from various clinical sources and results obtained from the MBT-CA System were compared to DNA sequencing and/or biochemical testing. Isolates that failed to report as a "high confidence species ID" [log(score) ≥2.00] were re-tested using an extraction method. The MBT-CA System identified 96.8% and 3.1% of isolates with either a "high confidence" or a "low confidence" [log(score) value between 1.70 and <2.00] species ID, respectively. Two isolates did not produce acceptable confidence scores after extraction. The MBT-CA System correctly identified 99.8% (2,258/2,263) to genus and 98.2% (2,222/2,263) to species level. These data demonstrate that the MBT-CA System provides accurate results for the identification of aerobic gram-negative bacteria.
Asunto(s)
Técnicas de Tipificación Bacteriana , Bacterias Aerobias Gramnegativas/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Técnicas de Tipificación Bacteriana/instrumentación , Técnicas de Tipificación Bacteriana/métodos , Bacterias Aerobias Gramnegativas/genética , Humanos , Sensibilidad y Especificidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/instrumentación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodosRESUMEN
A Gram-negative, aerobic, non-spore-forming, motile and ovoid or rod-shaped bacterial strain, designated MA2-16(T), was isolated from ark shell (Scapharca broughtonii) collected from the South Sea, South Korea. Strain MA2-16(T) was found to grow optimally at 30°C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain MA2-16(T) clustered with the type strain of Sedimentitalea nanhaiensis. The novel strain exhibited a 16S rRNA gene sequence similarity value of 97.1% to the type strain of S. nanhaiensis. In the neighbour-joining phylogenetic tree based on gyrB sequences, strain MA2-16(T) formed an evolutionary lineage independent of those of other taxa. Strain MA2-16(T) contained Q-10 as the predominant ubiquinone and C18:1 ω7c and 11-methyl C18:1 ω7c as the major fatty acids. The major polar lipids of strain MA2-16(T) were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid. The DNA G+C content of strain MA2-16(T) was 57.7 mol% and its DNA-DNA relatedness values with the type strains of S. nanhaiensis and some phylogenetically related species of the genera Leisingera and Phaeobacter were 13-24%. On the basis of the data presented, strain MA2-16(T) is considered to represent a novel genus and novel species within the family Rhodobacteraceae, for which the name Aliisedimentitalea scapharcae gen. nov., sp. nov. is proposed. The type strain is MA2-16(T) (=KCTC 42119(T) =CECT 8598(T)).
Asunto(s)
Bacterias Aerobias Gramnegativas/aislamiento & purificación , ARN Ribosómico 16S/clasificación , Rhodobacteraceae/clasificación , Scapharca/microbiología , Animales , Bacterias Aerobias Gramnegativas/clasificación , Filogenia , República de Corea , Rhodobacteraceae/genéticaRESUMEN
BACKGROUND: To determine clinical predictors and impact of Gram-negative nonfermenters (GNNFs) infections among adults with community-onset bacteremia in the emergency department (ED). METHODS: Adults with bacteremia visiting the ED from January 2007 to June 2008 were identified retrospectively. Demographic characteristics, underlying illnesses, clinical conditions, bacteremic pathogens, antimicrobial agents, and outcome, were retrieved from chart records. RESULTS: After the exclusion of 261 patients with contamination of blood cultures and 24 patients referred from other hospitals, 518 adults with community-onset bacteremia were eligible; their mean age was 65.1 years, with slight predominance of female (262 patients, 50.6%). Of a total of 565 bacteremic isolates, Escherichia coli (228 isolates, 40.4%) and Klebsiella pneumoniae (100, 17.7%) were the major microorganisms. GNNFs caused bacteremia in 31 (6.0%) patients. A higher proportion of inappropriate antibiotic therapy in the ED (87.1% vs. 26.5%, p < 0.001) and higher 28-day crude mortality rate (19.4% vs. 8.4%, p = 0.05) were observed in bacteremic patients caused by GNNFs than those not caused by GNNFs. In further analysis of Kaplan-Meier survival curve, patients with GNNF bacteremia had a worse outcome than those due to other pathogens (p = 0.04). Multivariate analysis revealed that the independent predictors related to GNNF bacteremia included surgery during previous 4 weeks prior to ED arrival [odds ratio (OR), 10.79; 95% confidence interval (CI), 1.84-63.24; p = 0.01], residents in long-term healthcare facilities (OR, 4.62; 95% CI, 2.08-10.29; p < 0.001), and malignancy (OR, 2.24; 95% CI, 1.10-5.40; p = 0.02). CONCLUSION: For adults with bacteremia visiting the ED, GNNF is associated with a higher mortality rate and more inappropriate empirical antibiotic therapy in the ED. To allow early administration of empirical antibiotics, several clinical predictors of GNNF infections were identified.
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Bacteriemia/epidemiología , Bacteriemia/microbiología , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Servicio de Urgencia en Hospital , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Adolescente , Adulto , Anciano , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/mortalidad , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/mortalidad , Quimioterapia/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
We present a unique case of acute bacterial prostatitis caused by a very rare human pathogen, Raoultella planticola, in a renal allograft recipient 3.5 months post transplantation. Only a few cases of human infection by this pathogen have been reported worldwide. The present study reports the case of a 67-year-old man who was admitted to our transplant unit 3.5 months post transplantation with fever, dysuria, suprapubic pain, symptoms and signs of acute prostatitis, and elevated markers of inflammation and prostate-specific antigen. R. planticola was isolated in the urine culture. The patient was treated with ciprofloxacin (based on the antibiogram) and had a full recovery, with satisfactory renal function. To the best of our knowledge, this is not only the first reported case of R. planticola prostatitis, but also the first report of such an infection in a solid organ transplant recipient or in a patient on immunosuppressive medication.
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Bacterias Aerobias Gramnegativas/clasificación , Infecciones por Bacterias Gramnegativas/microbiología , Trasplante de Riñón , Prostatitis/microbiología , Anciano , Antibacterianos/uso terapéutico , Ciprofloxacina/uso terapéutico , Humanos , Masculino , Prostatitis/tratamiento farmacológicoAsunto(s)
Bacterias Aerobias Gramnegativas/genética , Monosacáridos/metabolismo , ARN Ribosómico 16S/biosíntesis , Bacterias Reductoras del Azufre/fisiología , Microbiología del Agua , Composición de Base/genética , Medios de Cultivo , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Lagos/microbiología , Filogenia , ARN Ribosómico 16S/análisis , Siberia , Simbiosis , Temperatura , Ubiquinona/metabolismo , Vitamina K 2/metabolismoRESUMEN
The 16S-23S gene internal transcribed spacer sequence of sixty-four strains belonging to different acetic acid bacteria genera were analyzed, and phylogenetic trees were generated for each genera. The topologies of the different trees were in accordance with the 16S rRNA gene trees, although the similarity percentages obtained between the species was shown to be much lower. These values suggest the usefulness of including the 16S-23S gene internal transcribed spacer region as a part of the polyphasic approach required for the further classification of acetic acid bacteria. Furthermore, the region could be a good target for primer and probe design. It has also been validated for use in the identification of unknown samples of this bacterial group from wine vinegar and fruit condiments.
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Ácido Acético , Bacterias Aerobias Gramnegativas/genética , Técnicas de Tipificación Bacteriana , Secuencia de Bases , Microbiología de Alimentos , Genes de ARNr , Bacterias Aerobias Gramnegativas/clasificación , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S , ARN Ribosómico 23S , Análisis de Secuencia de ARNRESUMEN
In a retrospective study on the microbiology of minced meat from small food businesses supplying directly to the consumer, the relative contribution of meat supplier, meat species and outlet where meat was minced was assessed by "Classification and Regression Tree" (CART) analysis. Samples (n=888) originated from 129 outlets of a single supermarket chain. Sampling units were 4-5 packs (pork, beef, and mixed pork-beef). Total aerobic counts (TACs) were 5.3±1.0 log CFU/g. In 75.6% of samples, E. coli were <1 log CFU/g. The proportion of "unsatisfactory" sample sets [as defined in Reg. (EC) 2073/2005] were 31.3 and 4.5% for TAC and E. coli, respectively. For classification according to TACs, the outlet where meat was minced and the "meat supplier" were the most important predictors. For E. coli, "outlet" was the most important predictor, but the limit of detection of 1 log CFU/g was not discriminative enough to allow further conclusions.
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Técnicas de Tipificación Bacteriana , Bacterias Aerobias Gramnegativas/clasificación , Productos de la Carne/clasificación , Productos de la Carne/microbiología , Modelos Estadísticos , Animales , Bovinos , Recuento de Colonia Microbiana , Escherichia coli/clasificación , Escherichia coli/aislamiento & purificación , Unión Europea , Manipulación de Alimentos/métodos , Inspección de Alimentos/legislación & jurisprudencia , Abastecimiento de Alimentos/economía , Enfermedades Transmitidas por los Alimentos/prevención & control , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Productos de la Carne/economía , Productos de la Carne/normas , Industria para Empaquetado de Carne , Análisis de Regresión , Estudios Retrospectivos , Pequeña Empresa/legislación & jurisprudencia , Sus scrofaRESUMEN
A Gram-negative, non-spore-forming, endophytic bacterium, strain YC6886(T), was isolated from the root of a halophyte, Rosa rugosa, which inhabits coastal areas of Namhae Island off the southern coast of Korea. Cells were non-motile, obligately aerobic rods and formed pale-yellow colonies. The isolate grew at 4-32 °C (optimum 25-28 °C) and at pH 6.5-9.5 (optimum pH 7.5) and grew optimally with 2-3 % (w/v) NaCl, but NaCl was not an absolute requirement for growth. Strain YC6886(T) produced yellow carotenoid pigments. Strain YC6886(T) exhibited the highest 16S rRNA gene sequence similarity with Haloferula sargassicola MN1-1037(T) (97.4 %). Sequence similarities between strain YC6886(T) and other members of the genus Haloferula were 93.9-94.7 %. DNA-DNA relatedness between strain YC6886(T) and H. sargassicola KCTC 22202(T) and Haloferula rosea KCTC 22201(T) was 27 and 15 %, respectively. The major fatty acids were iso-C(14 : 0), C(16 : 0) and C(16 : 1)ω9c and minor components were C(14 : 0), C(18 : 0) and anteiso-C(15 : 0). The major respiratory quinone was menaquinone 9 and the DNA G+C content was 58.5 mol%. The polar lipid profile was composed of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unknown phospholipid and an unknown phosphoglycolipid. On the basis of phenotypic, chemotaxonomic, DNA-DNA hybridization and phylogenetic analysis, strain YC6886(T) represents a novel species in the genus Haloferula, for which the name Haloferula luteola sp. nov. is proposed. The type strain is YC6886(T) (â=âKCTC 22447(T) â= DSM 21608(T)). An emended description of the genus Haloferula is also presented.
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Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Raíces de Plantas/microbiología , Rosa/microbiología , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/metabolismo , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
Bryobacter aggregatus gen. nov., sp. nov. is proposed to accommodate three strains of slowly growing, chemo-organotrophic bacteria isolated from acidic Sphagnum peat bogs. These bacteria were strictly aerobic, Gram-negative, colourless, non-motile coccoids or short rods that multiplied by normal cell division and formed irregularly shaped cell aggregates. Strains MPL3(T), MPL1011 and MOB76 were acidotolerant, mesophilic organisms capable of growth at pH 4.5-7.2 and between 4 and 33 degrees C (optimum growth at pH 5.5-6.5 and 22-28 degrees C). The preferred growth substrates were sugars, some heteropolysaccharides and galacturonic and glucuronic acids, which are released during decomposition of Sphagnum moss. The major fatty acids were iso-C(15 : 0), C(16 : 0) and summed feature 3 (iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c); the major quinones were MK-9 and MK-10. The DNA G+C content was 55.5-56.5 mol%. Strains MPL3(T), MPL1011 and MOB76 possessed nearly identical 16S rRNA gene sequences and belonged to the phylum Acidobacteria. They represent the first taxonomically characterized members of acidobacterial subdivision 3 and display only 81.7-86.7 % 16S rRNA gene sequence similarity to other members of the Acidobacteria with validly published names. Therefore, strains MPL3(T), MPL1011 and MOB76 are classified as representatives of a novel species in a new genus, for which the name Bryobacter aggregatus gen. nov., sp. nov. is proposed; strain MPL3(T) (=ATCC BAA-1390(T) =DSM 18758(T)) is the type strain of Bryobacter aggregatus.
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Bacterias Aerobias Gramnegativas/clasificación , Microbiología del Suelo , Sphagnopsida/microbiología , Composición de Base , Secuencia de Bases , ADN Bacteriano/química , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/ultraestructura , Datos de Secuencia Molecular , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Homología de Secuencia de Ácido Nucleico , SiberiaRESUMEN
Industrial wastewater from the production of sulfur containing esters and the resulting products of this synthesis, 2-ethylhexylthioglycolic acid (EHTG) and iso-octylthioglycolic acid (IOTG), were deployed in this study to enrich novel bacterial strains, since no wastewater and EHTG or IOTG degrading microorganisms were hitherto described or available. In addition, nothing is known about the biodegradation of these thiochemicals. The effect of this specific wastewater on the growth behaviour of microorganisms was investigated using three well-known Gram-negative bacteria (Escherichia coli, Pseudomonas putida, and Ralstonia eutropha). Concentrations of 5% (v/v) wastewater in complex media completely inhibited growth of these three bacterial strains. Six bacterial strains were successfully isolated, characterized and identified by sequencing their 16S rRNA genes. Two isolates referred to as Achromobacter sp. strain MT-E3 and Pseudomonas sp. strain MT-I1 used EHTG or IOTG, respectively, as well as the wastewater as sole source of carbon and energy for weak growth. More notably, both isolates removed these sulfur containing esters in remarkable amounts from the cultures supernatant. One further isolate was referred to as Klebsiella sp. strain 58 and exhibited an unusual high tolerance against the wastewater's toxicity without utilizing the contaminative compounds. If cultivated with gluconic acid as additional carbon source, the strain grew even in presence of more than 40% (v/v) wastewater. Three other isolates belonging to the genera Bordetella and Pseudomonas tolerated these organic sulfur compounds but showed no degradation abilities.