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1.
ACS Appl Mater Interfaces ; 9(49): 43352-43362, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29143530

RESUMO

Spatiotemporal particle patterning in evaporating droplets lacks a common design framework. Here, we demonstrate autonomous control of particle distribution in evaporating droplets through the imposition of a salt-induced self-generated electric field as a generalized patterning strategy. Through modeling, a new dimensionless number, termed "capillary-phoresis" (CP) number, arises, which determines the relative contributions of electrokinetic and convective transport to pattern formation, enabling one to accurately predict the mode of particle assembly by controlling the spontaneous electric field and surface potentials. Modulation of the CP number allows the particles to be focused in a specific region in space or distributed evenly. Moreover, starting with a mixture of two different particle types, their relative placement in the ensuing pattern can be controlled, allowing coassemblies of multiple, distinct particle populations. By this approach, hypermethylated DNA, prevalent in cancerous cells, can be qualitatively distinguished from normal DNA of comparable molecular weights. In other examples, we show uniform dispersion of several particle types (polymeric colloids, multiwalled carbon nanotubes, and molecular dyes) on different substrates (metallic Cu, metal oxide, and flexible polymer), as dictated by the CP number. Depending on the particle, the highly uniform distribution leads to surfaces with a lower sheet resistance, as well as superior dye-printed displays.

2.
Sci Total Environ ; 379(2-3): 216-25, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17064754

RESUMO

Weathering of mine tailings in Adak results in high As concentrations in surface and ground water, sediments, and soil. In spite of the oxic conditions, As-rich surface and ground water samples indicate As(III) species predominantly (up to 83%). Several microorganisms were isolated from the enrichment cultures that were involved in As cycling. Amongst them was Arsenicicoccus bolidensis - a novel gram-positive, facultatively anaerobic, coccus-shaped actinomycete, which actively reduced As(V) to As(III) in aqueous media. A. bolidensis reduced 0.06-0.20 mM day(-1) As(V). As(V) reduction displays a direct correlation between the initial As(V) concentration, growth rate, and biomass yield.


Assuntos
Actinomycetales/metabolismo , Arsênio/metabolismo , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo , Actinomycetales/genética , Actinomycetales/crescimento & desenvolvimento , Arsênio/análise , Sequência de Bases , Biodegradação Ambiental , Monitoramento Ambiental , Sedimentos Geológicos/análise , Mineração , Dados de Sequência Molecular , Oxirredução , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rios/química , Análise de Sequência de DNA , Poluentes do Solo/análise , Sulfetos , Suécia , Poluentes Químicos da Água/análise
3.
Int J Syst Evol Microbiol ; 56(Pt 6): 1311-1316, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16738108

RESUMO

Phenotypic and phylogenetic studies were performed on three isolates of an unknown Gram-negative, facultatively anaerobic, non-motile, yellow-pigmented, rod-shaped organism isolated from raw sewage. 16S rRNA gene sequence analysis indicated that these strains were members of the Bergeyella-Chryseobacterium-Riemerella branch of the family Flavobacteriaceae. The unknown bacterium was readily distinguished from reference strains by 16S rRNA gene sequencing and biochemical tests. The organism contained menaquinone MK-6 as the predominant respiratory quinone and had a DNA G+C content of 31 mol%. A most probable number-PCR approach was developed to detect, and estimate the numbers of, this organism. Untreated wastewater from one plant yielded an estimated count of 1.4 x 10(5) cells ml(-1), and untreated wastewater from a second plant yielded an estimated count of 1.4 x 10(4) cells ml(-1). Signal was not detected from treated effluent or from human stool specimens. On the basis of the results of the study presented, it is proposed that the unknown bacterium be classified in a novel genus Cloacibacterium, as Cloacibacterium normanense gen. nov., sp. nov., which is also the type species. The type strain of Cloacibacterium normanense is strain NRS1(T) (=CCUG 46293(T) = CIP 108613(T) = ATCC BAA-825(T) = DSM 15886(T)).


Assuntos
Flavobacteriaceae/classificação , Eliminação de Resíduos Líquidos , Composição de Bases , DNA Bacteriano/química , Flavobacteriaceae/genética , Flavobacteriaceae/isolamento & purificação , Dados de Sequência Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Suécia , Microbiologia da Água
4.
Int J Syst Evol Microbiol ; 56(Pt 2): 429-432, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16449452

RESUMO

Two strains of an unknown Gram-positive, catalase-negative, facultatively anaerobic, coccus-shaped bacterium, originating from a porpoise and a grey seal, were characterized using phenotypic, biochemical and molecular phylogenetic methods. Chemical studies revealed the presence of a cell-wall murein based on L-lysine (type L-lys-gly-D-Asp) and a DNA G+C content of 38 mol%. Comparative 16S rRNA gene sequencing showed that this unidentified coccus-shaped organism formed a hitherto unknown subline closely related to, albeit distinct from, a number of other catalase-negative genera which included Enterococcus, Melissococcus, Tetragenococcus and Vagococcus. Other known Gram-positive, catalase-negative taxa were more distantly related. Tree-branching considerations and sequence divergence values of >6% with recognized taxa were indicative of this novel bacterium representing a separate genus. Based on phenotypic and phylogenetic evidence, it is proposed that this unknown bacterium, recovered from a porpoise and a grey seal, be classified as a novel genus and species, Catellicoccus marimammalium gen. nov., sp. nov. The type strain is M35/04/3T (=CCUG 49459T=CIP 108575T).


Assuntos
Catalase/metabolismo , Infecções por Bactérias Gram-Positivas/veterinária , Cocos Gram-Positivos/classificação , Toninhas/microbiologia , Focas Verdadeiras/microbiologia , Anaerobiose , Animais , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Genes de RNAr , Infecções por Bactérias Gram-Positivas/microbiologia , Cocos Gram-Positivos/genética , Cocos Gram-Positivos/isolamento & purificação , Cocos Gram-Positivos/fisiologia , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
6.
Syst Appl Microbiol ; 29(4): 292-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16337765

RESUMO

An obligatory anaerobic, Gram-positive, rod-shaped organism was isolated from faeces of a healthy human donor. It was characterized using biochemical, phenotypic and molecular taxonomic methods. The organism produced acetate, lactate, and ethanol as the major products of glucose fermentation. The G + C content was 53 mol%. Based on comparative 16S rRNA gene sequencing, the unidentified bacterium is a member of the Clostridium subphylum of the Gram-positive bacteria, and most closely related to species of the Clostridium coccoides cluster (rRNA cluster XIVa) [M.D. Collins et al., The phylogeny of the genus Clostridium: proposal of five new genera and eleven new species combinations, Int. J. Syst. Bacteriol. 44 (1994) 812-826]. Clostridium bolteae and Clostridium clostridioforme were identified as the most closely related described species. A 16S rRNA sequence divergence value of > 3% suggested that the isolate represents a new species. This was also supported by the gyrase-encoding gyrB gene sequences. Based on these findings, we propose the novel bacterium from human faeces to be classified as a new species, Clostridium asparagiforme. The type strain of C. asparagiforme is N6 (DSM 15981 and CCUG 48471).


Assuntos
Clostridium/classificação , Clostridium/isolamento & purificação , Fezes/microbiologia , Ácido Acético/metabolismo , Anaerobiose , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Clostridium/citologia , Clostridium/fisiologia , Infecções por Clostridium/microbiologia , DNA Girase/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Etanol/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Genes de RNAr/genética , Violeta Genciana , Glucose/metabolismo , Humanos , Ácido Láctico/metabolismo , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Fenazinas , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Int J Syst Evol Microbiol ; 55(Pt 6): 2269-2272, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16280481

RESUMO

Phenotypic and phylogenetic studies were performed on three strains of Gram-negative, rod-shaped organisms recovered from dead birds of the tit families (blue tit, coal tit and long-tailed tit). Morphological, cultural and biochemical studies indicated that the organisms were related to the family Cardiobacteriaceae in the gamma-subclass of the Proteobacteria. Comparative 16S rRNA gene sequencing studies confirmed these findings and demonstrated that the bacterium represents a hitherto unknown subline within this family. The closest phylogenetic relative of the strains isolated from the birds was found to be Suttonella indologenes, although a sequence divergence of approximately 5 % demonstrated that the unknown bacterium represented a novel species. On the basis of the results of the phylogenetic analysis and phenotypic criteria, it is proposed that the bacteria recovered from the diseased birds represent a novel species, Suttonella ornithocola sp. nov., with strain B6/99/2T (=CCUG 49457T=NCTC 13337T) as the type strain.


Assuntos
Aves/microbiologia , Cardiobacteriaceae/classificação , RNA Ribossômico 16S/análise , Animais , Cardiobacteriaceae/genética , Dados de Sequência Molecular , Fenótipo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Int J Syst Evol Microbiol ; 55(Pt 6): 2515-2518, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16280519

RESUMO

Two Gram-negative, anaerobic, non-spore-forming, rod-shaped organisms were isolated from a swine-manure storage pit. Based on morphological and biochemical criteria, the strains were tentatively identified as belonging to the genus Bacteroides but they did not appear to correspond to any recognized species of the genus. Comparative 16S rRNA gene sequencing studies showed that the strains were related closely to each other and confirmed their placement in the genus Bacteroides, but sequence divergence values of >10 % from reference Bacteroides species demonstrated that the organisms from manure represent a novel species. Based on biochemical criteria and molecular genetic evidence, it is proposed that the unknown isolates from manure be assigned to a novel species of the genus Bacteroides, as Bacteroides coprosuis sp. nov. The type strain is PC139T (=CCUG 50528T=NRRL B-41113T).


Assuntos
Bacteroides/isolamento & purificação , Esterco/microbiologia , Suínos/microbiologia , Animais , Bacteroides/classificação , Bacteroides/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
9.
Int J Syst Evol Microbiol ; 55(Pt 4): 1693-1696, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16014503

RESUMO

A novel Gram-positive, aerobic, catalase-negative, coccus-shaped organism originating from tobacco was characterized using phenotypic and molecular taxonomic methods. The organism contained a cell wall murein based on L-lysine (variation A4alpha, type L-lysine-L-glutamic acid), synthesized long-chain cellular fatty acids of the straight-chain saturated and monounsaturated types (with C(16:1)omega9, C(16:0) and C(18:1)omega9 predominating) and possessed a DNA G+C content of 46 mol%. Based on morphological, biochemical and chemical characteristics, the coccus-shaped organism did not conform to any presently recognized taxon. Comparative 16S rRNA gene sequencing studies confirmed the distinctiveness of the unknown coccus, with the bacterium displaying sequence divergence values of greater than 7% with other recognized Gram-positive taxa. Treeing analysis reinforced its distinctiveness, with the unidentified organism forming a relatively long subline branching at the periphery of an rRNA gene sequence cluster which encompasses the genera Alloiococcus, Allofustis, Alkalibacterium, Atopostipes, Dolosigranulum and Marinilactibacillus. Based on phenotypic and molecular phylogenetic evidence, it is proposed that the unknown organism from tobacco be classified as a new genus and species, Atopococcus tabaci gen. nov., sp. nov. The type strain of Atopococcus tabaci is CCUG 48253(T) (=CIP 108502(T)).


Assuntos
Catalase/metabolismo , Cocos Gram-Positivos/classificação , Nicotiana/microbiologia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Genes de RNAr , Cocos Gram-Positivos/química , Cocos Gram-Positivos/genética , Cocos Gram-Positivos/isolamento & purificação , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
J Clin Microbiol ; 43(7): 3526-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16000497

RESUMO

We report the isolation and characterization of a hitherto unknown gram-negative, rod-shaped Neisseria-like organism from an infected wound resulting from a bite from a kinkajou. Based on both phenotypic and phylogenetic evidence, it is proposed that the unknown organism be classified as a new species, Kingella potus sp. nov.


Assuntos
Mordeduras e Picadas , Carnívoros , Kingella/classificação , Infecções por Neisseriaceae/microbiologia , Infecção dos Ferimentos/microbiologia , Animais , DNA Ribossômico/análise , Genes de RNAr , Kingella/genética , Kingella/isolamento & purificação , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Appl Environ Microbiol ; 71(7): 4153-5, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16000838

RESUMO

The composition of the colonic microbiota of 91 northern Europeans was characterized by fluorescent in situ hybridization using 18 phylogenetic probes. On average 75% of the bacteria were identified, and large interindividual variations were observed. Clostridium coccoides and Clostridium leptum were the dominant groups (28.0% and 25.2%), followed by the Bacteroides (8.5%). According to principal component analysis, no significant grouping with respect to geographic origin, age, or gender was observed.


Assuntos
Bacteroides , Clostridium , Colo/microbiologia , Adolescente , Adulto , Bacteroides/classificação , Bacteroides/genética , Bacteroides/isolamento & purificação , Criança , Clostridium/classificação , Clostridium/genética , Clostridium/isolamento & purificação , Europa (Continente) , Citometria de Fluxo , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Análise Multivariada
12.
Int J Syst Evol Microbiol ; 55(Pt 3): 1243-1246, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15879263

RESUMO

Morphological, biochemical and molecular genetic studies were carried out on an unknown non-spore-forming, Gram-positive, rod-shaped bacterium that was isolated from dog faeces. The bacterium grew under strictly anaerobic conditions, was asaccharolytic, and possessed a relatively high G + C content of 61 mol%. Phylogenetic analysis based on comparative 16S rRNA gene sequencing showed that the unidentified bacterium was a member of the family Coriobacteriaceae and represents a hitherto unknown subline within the genus Slackia. Based on the presented findings, a novel species, Slackia faecicanis sp. nov., is described. The type strain of Slackia faecicanis is 5WC12(T) (= CCUG 48399(T) = CIP 108281(T)).


Assuntos
Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Cães/microbiologia , Fezes/microbiologia , Actinobacteria/citologia , Actinobacteria/fisiologia , Anaerobiose , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Genes Bacterianos , Genes de RNAr , Dados de Sequência Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Int J Syst Evol Microbiol ; 55(Pt 2): 843-846, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15774672

RESUMO

A previously undescribed, Gram-positive, catalase-negative, Streptococcus-like organism originating from a European beaver (Castor fiber) was subjected to a taxonomic study. The organism displayed beta-haemolytic activity and gave a positive reaction with Lancefield group A antisera. Based on the results of biochemical testing, the organism was tentatively identified as a member of the genus Streptococcus, but it did not correspond phenotypically to any recognized species of this genus. Comparative 16S rRNA gene sequencing studies confirmed this assignment, with the bacterium forming a hitherto unknown subline within the genus. Sequence divergence values of greater than 3 % from other reference streptococcal species, however, demonstrated that the unidentified coccus-shaped organism represents a hitherto unknown species. Based on phenotypic and molecular phylogenetic evidence, it is therefore proposed that the unknown organism from a beaver be classified as a novel species, Streptococcus castoreus sp. nov. The type strain is M605815/03/2(T) (=CCUG 48115(T)=CIP 108205(T)).


Assuntos
Mordeduras e Picadas/complicações , Roedores/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/classificação , Infecção dos Ferimentos/veterinária , Animais , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Cães , Genes de RNAr , Humanos , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Infecção dos Ferimentos/microbiologia
14.
Int J Syst Evol Microbiol ; 55(Pt 2): 853-858, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15774674

RESUMO

Phenotypic and phylogenetic studies were performed on two strains of an unidentified Gram-positive, fastidious, non-spore-forming, coccus-shaped bacterium recovered from human blood. The organism was catalase-negative and grew under strictly anaerobic conditions and in the presence of 2 and 6 % O(2). Comparative 16S rRNA gene sequencing demonstrated that the unidentified bacterium was, phylogenetically, far removed from peptostreptococci and related Gram-positive coccus-shaped organisms, but exhibited a phylogenetic association with Clostridium rRNA cluster III [as defined by Collins et al., Int J Syst Bacteriol 44 (1994), 812-826]. Sequence divergence values of 15 % or more were observed between the unidentified bacterium and all other recognized species within this and related rRNA clostridial clusters. Treeing analysis showed that the unknown bacterium formed a deep line branching at the periphery of rRNA cluster III and represents a hitherto unknown genus within this supra-generic grouping. On the basis of both phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium from blood be classified in a new genus, Fastidiosipila gen. nov., as Fastidiosipila sanguinis sp. nov. The type strain of Fastidiosipila sanguinis is CCUG 47711(T) (=CIP 108292(T)).


Assuntos
Sangue/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Cocos Gram-Positivos/classificação , Cocos Gram-Positivos/genética , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/microbiologia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Genes de RNAr , Cocos Gram-Positivos/crescimento & desenvolvimento , Cocos Gram-Positivos/isolamento & purificação , Humanos , Masculino , Dados de Sequência Molecular , Fenótipo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Appl Environ Microbiol ; 71(2): 636-45, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15691912

RESUMO

Phenotypically, Photobacterium damselae subsp. piscicida and P. damselae subsp. damselae are easily distinguished. However, their 16S rRNA gene sequences are identical, and attempts to discriminate these two subspecies by molecular tools are hampered by their high level of DNA-DNA similarity. The 16S-23S rRNA internal transcribed spacers (ITS) were sequenced in two strains of Photobacterium damselae subsp. piscicida and two strains of P. damselae subsp. damselae to determine the level of molecular diversity in this DNA region. A total of 17 different ITS variants, ranging from 803 to 296 bp were found, some of which were subspecies or strain specific. The largest ITS contained four tRNA genes (tDNAs) coding for tRNA(Glu(UUC)), tRNA(Lys(UUU)), tRNA(Val(UAC)), and tRNA(Ala(GGC)). Five amplicons contained tRNA(Glu(UUC)) combined with two additional tRNA genes, including tRNA(Lys(UUU)), tRNA(Val(UAC)), or tRNA(Ala(UGC)). Five amplicons contained tRNA(Ile(GAU)) and tRNA(Ala(UGC)). Two amplicons contained tRNA(Glu(UUC)) and tRNA(Ala(UGC)). Two different isoacceptor tRNA(Ala) genes (GGC and UGC anticodons) were found. The five smallest amplicons contained no tRNA genes. The tRNA-gene combinations tRNA(Glu(UUC))-tRNA(Val(UAC))-tRNA(Ala(UGC)) and tRNA(Glu(UUC))-tRNA(Ala(UGC)) have not been previously reported in bacterial ITS regions. The number of copies of the ribosomal operon (rrn) in the P. damselae chromosome ranged from at least 9 to 12. For ITS variants coexisting in two strains of different subspecies or in strains of the same subspecies, nucleotide substitution percentages ranged from 0 to 2%. The main source of variation between ITS variants was due to different combinations of DNA sequence blocks, constituting a mosaic-like structure.


Assuntos
DNA Espaçador Ribossômico/análise , Variação Genética , Photobacterium/classificação , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Sequência de Bases , DNA Bacteriano/análise , DNA Espaçador Ribossômico/genética , Dados de Sequência Molecular , Photobacterium/genética , RNA de Transferência/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie , Óperon de RNAr
16.
Int J Syst Evol Microbiol ; 55(Pt 1): 41-47, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653851

RESUMO

A Gram-negative, aerobic to microaerophilic rod was isolated from 10 m depths of the hypersaline, heliothermal and meromictic Ekho Lake (East Antarctica). The strain was oxidase- and catalase-positive, metabolized a variety of carboxylic acids and sugars and produced lipase. Cells had an absolute requirement for artificial sea water, which could not be replaced by NaCl. A large in vivo absorption band at 870 nm indicated production of bacteriochlorophyll a. The predominant fatty acids of this organism were 16 : 0 and 18 : 1omega7c, with 3-OH 10 : 0, 16 : 1omega7c and 18 : 0 in lower amounts. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine. Ubiquinone 10 was produced. The DNA G+C content was 67 mol%. 16S rRNA gene sequence comparisons indicated that the isolate represents a member of the Roseobacter clade within the alpha-Proteobacteria. The organism showed no particular relationship to any members of this clade but clustered on the periphery of the genera Jannaschia, Octadecabacter and 'Marinosulfonomonas' and the species Ruegeria gelatinovorans. Distinct morphological, physiological and genotypic differences to these previously described taxa supported the description of a new genus and a novel species, for which the name Roseisalinus antarcticus gen. nov., sp. nov. is proposed. The type strain is EL-88T (=DSM 11466T=CECT 7023T).


Assuntos
Bacterioclorofila A/biossíntese , Água Doce/microbiologia , Rhodobacteraceae/classificação , Aerobiose , Regiões Antárticas , Técnicas de Tipagem Bacteriana , DNA Ribossômico/análise , Genes de RNAr , Genótipo , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Rhodobacteraceae/metabolismo , Análise de Sequência de DNA , Cloreto de Sódio
17.
Int J Syst Evol Microbiol ; 55(Pt 1): 271-274, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653886

RESUMO

Two strains of an unidentified, Gram-positive, catalase-negative, chain-forming, coccus-shaped organism recovered from seals were characterized using phenotypic and molecular taxonomic methods. Based on morphological and biochemical criteria the strains were tentatively identified as streptococci but they did not appear to correspond to any recognized species of the genus Streptococcus. Comparative 16S rRNA gene sequencing studies showed that the strains were closely related to each other and confirmed their placement in the genus Streptococcus. Sequence divergence values of >5 % with reference streptococcal species demonstrated the organisms from seals represent a novel species. SDS-PAGE analysis of whole-cell proteins confirmed that the two organisms were closely related to each other but were different from all currently defined streptococcal species. Based on biochemical criteria, molecular chemical and molecular genetic evidence, it is proposed that the unknown isolates from seals be assigned to a novel species of the genus Streptococcus, Streptococcus marimammalium sp. nov. The type strain is M54/01/1T (=CCUG 48494T=CIP 108309T).


Assuntos
Phoca/microbiologia , Focas Verdadeiras/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/classificação , Streptococcus/isolamento & purificação , Animais , Proteínas de Bactérias/análise , Técnicas de Tipagem Bacteriana , DNA Ribossômico/análise , Eletroforese em Gel de Poliacrilamida , Genes de RNAr , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Infecções Estreptocócicas/microbiologia , Streptococcus/química , Streptococcus/genética
18.
Int J Syst Evol Microbiol ; 55(Pt 1): 427-431, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653913

RESUMO

A previously undescribed filamentous, beaded, Gram-positive, rod-shaped bacterium was isolated from pus of a human dental abscess. Based on its cellular morphology and the results of biochemical testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a distinct subline within the genus Actinomyces, clustering within a group of species that includes Actinomyces bovis, the type species of the genus. Sequence divergence values of >8 % with other recognized species within this phylogenetic group clearly demonstrated that the organism represents a hitherto unknown species. Based on biochemical and molecular phylogenetic evidence, it is proposed that the unidentified organism recovered from a dental abscess be classified as a novel species, Actinomyces dentalis sp. nov. The type strain is R18165T (=CCUG 48064T=CIP 108337T).


Assuntos
Abscesso/microbiologia , Actinomyces/classificação , Actinomyces/isolamento & purificação , Doenças Dentárias/microbiologia , Actinomyces/genética , Actinomyces/metabolismo , Actinomicose/microbiologia , Idoso , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Feminino , Genes de RNAr , Humanos , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
19.
Dis Aquat Organ ; 61(1-2): 33-9, 2004 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-15584408

RESUMO

The 23S ribosomal RNA (rRNA) gene has been sequenced in strains of the fish pathogens Photobacterium damselae subsp. damselae (ATCC 33539) and subsp. piscicida (ATCC 29690), showing that 3 nucleotide positions are clearly different between subspecies. In addition, the 5S rRNA gene plus the intergenic spacer region between the 23S and 5S rRNA genes (ITS-2) were amplified, cloned and sequenced for the 2 reference strains as well as the field isolates RG91 (subsp. damselae) and DI21 (subsp. piscicida). A 100% similarity was found for the consensus 5S rRNA gene sequence in the 2 subspecies, although some microheterogeneity was detected as inter-cistronic variability within the same chromosome. Sequence analysis of the spacer region between the 23S and 5S rRNA genes revealed 2 conserved and 3 variable nucleotide sequence blocks, and 4 different modular organizations were found. The ITS-2 spacer region exhibited both inter-subspecies and intercistronic polymorphism, with a mosaic-like structure. The EMBL accession numbers for the 23S, 5S and ITS-2 sequences are: P. damselae subsp. piscicida 5S gene (AJ274379), P. damselae subsp. damselae 23S gene (Y18520), subsp. piscicida 23S gene (Y17901), P. damselae subsp. piscicida ITS-2 (AJ250695, AJ250696), P. damselae subsp. damselae ITS-2 (AJ250697, AJ250698).


Assuntos
DNA Espaçador Ribossômico/genética , Variação Genética , Photobacterium/genética , Filogenia , Sequência de Bases , Análise por Conglomerados , Primers do DNA , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
20.
Int J Syst Evol Microbiol ; 54(Pt 6): 2291-2296, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15545473

RESUMO

Six isolates of an unknown Gram-positive, catalase-negative, chain-forming, coccus-shaped organism isolated from ovine and caprine mastitis were characterized by phenotypic and molecular taxonomic methods. On the basis of cellular morphology and the results of biochemical tests, the organism was tentatively identified as a streptococcal species. Comparative 16S rRNA gene sequencing studies confirmed that the organism is a member of the genus Streptococcus, with Streptococcus equi as its closest phylogenetic relative (98.8 % similarity). DNA-DNA pairing studies showed that the unidentified organism displayed more than 70 % relatedness to the type strains of S. equi subsp. equi and subsp. zooepidemicus. Despite the relatively high DNA-DNA reassociation values, biotyping and ribotyping allowed clear differentiation of the unknown bacterium from the two recognized subspecies of S. equi. On the basis of phenotypic and molecular genetic evidence, it is proposed that the unknown Streptococcus isolates from ovine and caprine mastitis be classified as a novel subspecies, Streptococcus equi subsp. ruminatorum subsp. nov. The type strain is CECT 5772(T) (=CCUG 47520(T)=Mt 167(T)).


Assuntos
Mastite/veterinária , Ruminantes/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus equi/classificação , Streptococcus equi/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Catalase/análise , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Genes de RNAr , Violeta Genciana , Doenças das Cabras/microbiologia , Cabras , Mastite/microbiologia , Dados de Sequência Molecular , Fenazinas , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Ribotipagem , Análise de Sequência de DNA , Ovinos , Doenças dos Ovinos/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus equi/citologia , Streptococcus equi/fisiologia
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