RESUMEN
Kiritimatiellaeota is widespread and ecologically important in various anoxic environments. However, the portion of culturable bacteria within this phylum is quite low and, in fact, there is only one currently described species. In this study, a novel anaerobic, non-motile, coccoid, Gram-stain-negative bacterial strain, designated S-5007T, was isolated from surface marine sediment. The 16S rRNA gene sequence was found to have very low 16S rRNA gene sequence similarity to the nearest known type strain, Kiritimatiella glycovorans L21-Fru-ABT (84.9 %). The taxonomic position of the novel isolate was investigated using a polyphasic approach and comparative genomic analysis. Phylogenetic analyses based on 16S rRNA genes and genomes indicated that strain S-5007T branched within the radiation of the phylum Kiritimatiellaeota. Different from the type strain, strain S-5007T can grow under microaerobic conditions, and the genomes of strain S-5007T and the other strains in its branch have many more antioxidant-related genes. Meanwhile, other different metabolic features deduced from genome analysis supported the separate evolution of the proposed class (strain S-5007T branch) and K. glycovorans L21-Fru-ABT. Based on phylogenetic and phenotypic characterization studies, Tichowtungia aerotolerans gen. nov., sp. nov. is proposed with S-5007T (=MCCC 1H00402T=KCTC 15876T) as the type strain, as the ï¬rst representative of novel taxa, Tichowtungiales ord. nov., Tichowtungiaceae fam. nov. in Tichowtungiia class. nov.
Asunto(s)
Sedimentos Geológicos/microbiología , Cocos Anaerobios Gramnegativos/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Cocos Anaerobios Gramnegativos/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Three strains, FYK2301M01(T), FYK2301M18 and FYK2301M52, all being Gram-negative, spherical, motile and facultatively anaerobic, were isolated from a marine alga (Porphyra sp.) collected on Mikura Island, Japan. Colonies of the strains were circular and pink-pigmented on Marine Agar 2216 (Difco) at 25 degrees C. Cells of the strains reproduced by binary fission. The G+C content of the DNA was 73 mol%. The major isoprenoid quinone was MK-6. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strains are the members of the WPS-1 group (Nogales et al., 2001) comprising no validly described taxa within the phylum Planctomycetes. The highest similarity value of the 16S rRNA gene sequences of the strains to those in the established bacterial taxa was only 78.7% to Planctomyces brasiliensis DSM 5305(T). From the taxonomic data obtained in this study, it is proposed that the new marine isolates be placed in a novel genus and species named Phycisphaera mikurensis gen. nov., sp. nov. within a new family, order and class Phycisphaeraceae fam. nov., Phycisphaerales ord. nov. and Phycisphaerae classis nov. in the phylum Planctomycetes. The type strain of Phycisphaera mikurensis is FYK2301M01(T) (= NBRC 102666(T) = KCTC 22515(T)).
Asunto(s)
Cocos Anaerobios Gramnegativos/clasificación , Cocos Anaerobios Gramnegativos/aislamiento & purificación , Porphyra/microbiología , Microbiología del Agua , Composición de Base , ADN Bacteriano/análisis , ADN Bacteriano/genética , Cocos Anaerobios Gramnegativos/genética , Cocos Anaerobios Gramnegativos/ultraestructura , Japón , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
A novel strictly anaerobic, cellobiose-degrading bacterium, strain CelloT, was isolated from a human faecal sample by combining enrichments in liquid and soft-agar basal media. A noteworthy characteristic was its inability to grow on normal agar plates and in roll tubes. The cells were coccus shaped and non-motile, with an extracellular slime layer. Growth of strain CelloT occurred between 20 and 40degrees C, with optimal growth at 37 degrees C. The pH range for growth was 5-7.5 with an optimum at 6.5. In pure culture, strain CelloT could only grow on a variety of sugars. Glucose was converted to acetate, ethanol and H2. The doubling time on glucose was 0.5 h. In a syntrophic co-culture with Methanospirillum hungatei strain JF-1T, strain CelloT converted glucose to acetate and H2. The G+C content was 59.2 mol%. 16S rDNA analysis revealed that the closest relatives of strain CelloT were two uncultured bacteria from anaerobic digesters, both with 94% 16S rDNA sequence similarity. The closest cultured representatives belong to genera of the bacterial division 'Verrucomicrobia'. The name Victivallis vadensis gen. nov., sp. nov. is proposed for strain CelloT (=DSM 14823T =ATCC BAA-548T).
Asunto(s)
Cocos Anaerobios Gramnegativos/clasificación , Cocos Anaerobios Gramnegativos/metabolismo , Composición de Base , Metabolismo de los Hidratos de Carbono , Celobiosa/metabolismo , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/genética , Heces/microbiología , Fermentación , Cocos Anaerobios Gramnegativos/genética , Cocos Anaerobios Gramnegativos/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genéticaRESUMEN
Megasphaera cerevisiae is a Gram-negative obligate anaerobe that causes turbidity and off-flavour and aroma in beer. Seven isolates of M. cerevisiae were obtained worldwide, and their extractable surface antigens were focused upon to determine if there is more than one serogroup of this bacterium. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of ethylenediaminetetraacetic acid (EDTA) bacterial extracts revealed a predominant protein with apparent molecular weights of 46,000, 45,000, and 43,000 for three, two, and two isolates, respectively. When mouse anti-serum generated against any of the EDTA extracts was reacted with denatured bacterial proteins in immunoblots, all bacterial isolates exhibited extensive cross-reactivity involving three antigens, one being the major EDTA-extractable protein. In contrast, when the sera were tested for surface reactivity with intact bacteria, three cross-reactivity groups were observed, with the groups individually comprised of bacteria having the same size major EDTA-extractable surface protein. When BALB/c mice immunized with a bacterium from each of the three serogroups were used for monoclonal antibody (Mab) hybridoma production, bacterial surface-reactive Mabs were obtained whose reactivities parallel the three polyclonal antibody-defined serogroups. Through combining these surface-reactive Mabs, it will be possible to rapidly detect and identify beer contamination by M. cerevisiae belonging to any serogroup.
Asunto(s)
Antígenos Bacterianos/aislamiento & purificación , Cerveza/microbiología , Cocos Anaerobios Gramnegativos/clasificación , Animales , Anticuerpos Antibacterianos/biosíntesis , Anticuerpos Monoclonales/biosíntesis , Especificidad de Anticuerpos , Antígenos Bacterianos/química , Antígenos Bacterianos/inmunología , Antígenos de Superficie , Ácido Edético , Electroforesis en Gel de Poliacrilamida , Fluoroinmunoensayo , Cocos Anaerobios Gramnegativos/inmunología , Hibridomas , Immunoblotting , Ratones , Ratones Endogámicos BALB C , Peso Molecular , SerotipificaciónRESUMEN
Lautropia mirabilis, a pleomorphic, motile, gram-negative coccus, has been isolated from the oral cavities of 32 of 60 (53.3%) children infected with human immunodeficiency virus (HIV) and 3 of 25 (12.0%) HIV-uninfected controls; the association of L. mirabilis isolation with HIV infection is significant (P < 0.001). All children in the study, both HIV-infected children and controls, were born to HIV-infected mothers. The presence of this bacterium was not associated with clinical disease in these children. The HIV-infected children with L. mirabilis did not differ from the HIV-infected children without L. mirabilis in immunological status, clinical status, or systemic medications. The role of HIV infection itself or concomitant factors in the establishment of L. mirabilis in the oral cavity remains to be elucidated.
Asunto(s)
Encía/microbiología , Cocos Anaerobios Gramnegativos/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/complicaciones , Infecciones por VIH/complicaciones , Mucosa Bucal/microbiología , Niño , Preescolar , Femenino , Cocos Anaerobios Gramnegativos/clasificación , Cocos Anaerobios Gramnegativos/crecimiento & desarrollo , Cocos Anaerobios Gramnegativos/ultraestructura , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Lactante , Recién Nacido , Masculino , Microscopía ElectrónicaRESUMEN
The current knowledge is reviewed concerning the anaerobic cocci, in particular those of clinical relevance. The anaerobic cocci are defined and their current taxonomic positions discussed. It is clear that new genera and species await to be characterised fully. The overwhelming majority found in clinical material belong to the genus Peptostreptococcus, with the remainder belonging to the veillonellae and, possibly, ruminococci. Human infections with other anaerobic cocci are extremely rare. Their morphology, metabolism and culture, and role in clinical infections are assessed. The methods for isolation and identification, which for some species are difficult, are presented, together with brief summaries of the clinically important species. The review concludes with the current status of antibiotic susceptibilities and the methods used to test susceptibility in vitro. There is no current consensus as to which susceptibility test method is the method of choice.
Asunto(s)
Cocos Anaerobios Gramnegativos/clasificación , Cocos Grampositivos/clasificación , Cocos Anaerobios Gramnegativos/aislamiento & purificación , Cocos Anaerobios Gramnegativos/patogenicidad , Cocos Grampositivos/aislamiento & purificación , Cocos Grampositivos/patogenicidad , Humanos , Pruebas de Sensibilidad Microbiana , Peptostreptococcus/clasificaciónRESUMEN
An organism that seems to be identical to Orskov's 'Sarcina mirabilis' [Orskov, J. (1930) Acta Pathol Microbiol Scand Suppl III, 519-541] has been rediscovered in specimens from the upper respiratory tract of humans. Six strains were studied, and the results, which conformed to Orskov's description of S. mirabilis, were as follows. Rough to smooth colonies grow on many plated media and show extremely polymorphic cell morphology with round cells with diameters from 1 to > 10 microns. The smallest cells were often motile with circular movements. Strains were Gram-negative, facultatively anaerobic, oxidase and urease positive, and weakly catalase positive. Nitrate and nitrite were reduced, and glucose, fructose, sucrose and mannitol were fermented. Polysaccharide was produced on sucrose agar. Electron microscopy showed coccoid cells with a bundle of three to nine flagella, a Gram-negative cell-wall morphology, and aggregates of irregular cells held together by a common surface layer. The mean mol% (G+C) of the organisms was 65.0. 16S-ribosomal RNA sequencing revealed that the organism belongs to the beta subgroup of Proteobacteria, separate from all other described genera, but most closely related to Burkholderia. The name Lautropia mirabilis is proposed for this organism.
Asunto(s)
Cocos Anaerobios Gramnegativos/clasificación , Cocos Anaerobios Gramnegativos/aislamiento & purificación , Boca/microbiología , Técnicas de Tipificación Bacteriana , División Celular , Movimiento Celular , Cocos Anaerobios Gramnegativos/genética , Cocos Anaerobios Gramnegativos/ultraestructura , Humanos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
This article provides an overview of the antimicrobial agents most commonly employed against the bacteria that cause infections in the ear, nose, throat, head, and neck. Because new bacterial resistances appear so regularly, as do new antibiotics, the reader is encouraged to supplement the information provided within this article with current information from the available literature. Specific treatment strategies for both acute and chronic sinusitis also are reviewed.
Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Enfermedades de los Senos Paranasales/microbiología , Sinusitis/tratamiento farmacológico , Antibacterianos/clasificación , Antibacterianos/farmacología , Infecciones Bacterianas/microbiología , Farmacorresistencia Microbiana , Femenino , Cocos Anaerobios Gramnegativos/clasificación , Cocos Anaerobios Gramnegativos/efectos de los fármacos , Cocos Anaerobios Gramnegativos/aislamiento & purificación , Humanos , Masculino , Enfermedades Otorrinolaringológicas/tratamiento farmacológico , Enfermedades Otorrinolaringológicas/microbiología , Enfermedades de los Senos Paranasales/tratamiento farmacológico , Sinusitis/microbiología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus pyogenes/efectos de los fármacos , Streptococcus pyogenes/aislamiento & purificaciónRESUMEN
Quin's oval is a relatively large bacterium often seen in the rumens of sheep fed diets containing some readily fermented carbohydrates. It has not been obtained in axenic cultures, but a number of its features have been determined by various methods, such as studying cell suspensions purified from rumen fluid by differential centrifugation. We obtained similarly purified suspensions from a sheep fed a diet containing a large amount of molasses. Nearly complete 16S rRNA sequence analysis of these cells as well as cells as Selenomonas ruminantium subsp. ruminantium GA192 (ATCC 12561; type strain) and S. ruminantium subsp. lactilytica HD4 (ATCC 27209) was done. These sequences were compared with those of other bacteria. Evolutionary distance estimates indicated that Quin's oval was most closely related to the Selenomonas-Megasphaera-Sporomusa group in the gram-positive phylum but that it belongs in a new genus. We propose the name Quinella ovalis gen. nov., sp. nov., with its description based on previously known features.
Asunto(s)
Bacterias Anaerobias Gramnegativas/clasificación , Animales , Secuencia de Bases , Cocos Anaerobios Gramnegativos/clasificación , Datos de Secuencia Molecular , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Rumen/microbiología , Ovinos/microbiologíaRESUMEN
Two kinds of predatory bacteria have been observed and characterized by light and electron microscopy in samples from freshwater sulfurous lakes in northeastern Spain. The first bacterium, named Vampirococcus, is Gram-negative and ovoidal (0.6 micrometer wide). An anaerobic epibiont, it adheres to the surface of phototrophic bacteria (Chromatium spp.) by specific attachment structures and, as it grows and divides by fission, destroys its prey. An important in situ predatory role can be inferred for Vampirococcus from direct counts in natural samples. The second bacterium, named Daptobacter, is a Gram-negative, facultatively anaerobic straight rod (0.5 x 1.5 micrometers) with a single polar flagellum, which collides, penetrates, and grows inside the cytoplasm of its prey (several genera of Chromatiaceae). Considering also the well-known case of Bdellovibrio, a Gram-negative, aerobic curved rod that penetrates and divides in the periplasmic space of many chemotrophic Gram-negative bacteria, there are three types of predatory prokaryotes presently known (epibiotic, cytoplasmic, and periplasmic). Thus, we conclude that antagonistic relationships such as primary consumption, predation, and scavenging had already evolved in microbial ecosystems prior to the appearance of eukaryotes. Furthermore, because they represent methods by which prokaryotes can penetrate other prokaryotes in the absence of phagocytosis, these associations can be considered preadaptation for the origin of intracellular organelles.