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1.
Microbiol Resour Announc ; 11(8): e0054622, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35862924

RESUMO

Pseudomonas protegens strain MWU12-2233 was isolated from wild cranberry fruit surfaces in Provincetown, MA. The genome contains putative hydrogen cyanide synthase and type VI secretion systems which can act symbiotically on plant health by suppressing competitors, indicating a role in indigenous microfloral disease and insect pest suppression.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35699988

RESUMO

Two non-pigmented strains in the genus Chromobacterium, MWU14-2602T and MWU13-2610T, were isolated from wild cranberry bogs in the Cape Cod National Seashore, USA. The isolates were characterized by genomic and phenotypic analyses, the results of which indicated that they represent two novel species. Based on total genome sequences, the closest relatives were in the Chromobacterium amazonense group, which includes the recently described Chromobacterium paludis. Whole genome sequences were compared by genome blast distance phylogeny, digital DNA-DNA hybridization and average nucleotide identity analyses with each other and with the type strains of their nearest species. MWU14-2602T and MWU13-2610T fell well below the accepted cutoff values for species relatedness, clearly indicating that they represent novel species. Although little is known about these organisms in situ, under laboratory conditions, MWU13-2610T produced a modest amount of HCN and was strongly positive for exoprotease activity, whereas MWU14-2602T did not produce HCN or exoproteases. The predominant fatty acids for both isolates were summed C16 : 1ω7cis/C16 : 1ω6cis. Both isolates produced siderophores and pyomelanin pigment on rich media, and neither was haemolytic on sheep blood agar. We propose the names Chromobacterium alticapitis sp. nov. (type strain MWU14-2602T=ATCC TSD 260T=CCOS 1979T) and Chromobacterium sinusclupearum sp. nov. (type strain MWU13-2610T=ATCC TSD-259T=CCOS 1981T) for these taxa.


Assuntos
Chromobacterium , Vaccinium macrocarpon , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ovinos , Vaccinium macrocarpon/genética , Áreas Alagadas
3.
Microbiol Resour Announc ; 10(27): e0020421, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236228

RESUMO

The surfaces of plants are colonized by a rich diversity of microbes but are largely unexplored. Here, we present the draft genome sequences of five Pseudomonas spp. isolated from cultivated cranberry fruit surfaces. Although the isolates represent four different species, their genomes all contain conserved iron sequestration and uptake genes.

4.
AMB Express ; 10(1): 202, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33159606

RESUMO

The precipitous drop in the cost of genomic sequencing and the concomitant availability of computational methods for comparing genome-level data has made the accurate taxonomic placement of bacteria affordable and relatively rapid. Inaccurate taxonomic placement of bacteria has serious implications in clinical, environmental, and regulatory microbiology, but it can also adversely affect interpretation of research results. The quorum biosensor strain CV026 was derived from an isolate of Chromobacterium that was labeled as C. violaceum ATCC 31532, and is catalogued by the ATCC under that species name. Nearly 200 papers have been published that use CV026 as an indicator for quorum sensing activity in many Gram negative bacteria, but the inability of C. violaceum strains to complement the quorum sensing mutation in CV026 has called the taxonomic placement of the parent strain into question. We used molecular phylogeny and a large number of metabolic and phenotypic characters to demonstrate that Chromobacterium strain ATCC 31532 is a member of species Chromobacterium subtsugae.

5.
Front Microbiol ; 11: 1035, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508802

RESUMO

The study of chemical bioactivity in the rhizosphere has recently broadened to include microbial metabolites, and their roles in niche construction and competition via growth promotion, growth inhibition, and toxicity. Several prior studies have identified bacteria that produce volatile organic compounds (VOCs) with antifungal activities, indicating their potential use as biocontrol organisms to suppress phytopathogenic fungi and reduce agricultural losses. We sought to expand the roster of soil bacteria with known antifungal VOCs by testing bacterial isolates from wild and cultivated cranberry bog soils for VOCs that inhibit the growth of four common fungal and oomycete plant pathogens, and Trichoderma sp. Twenty one of the screened isolates inhibited the growth of at least one fungus by the production of VOCs, and isolates of Chromobacterium vaccinii had broad antifungal VOC activity, with growth inhibition over 90% for some fungi. Fungi exposed to C. vaccinii VOCs had extensive morphological abnormalities such as swollen hyphal cells, vacuolar depositions, and cell wall alterations. Quorum-insensitive cviR - mutants of C. vaccinii were significantly less fungistatic, indicating a role for quorum regulation in the production of antifungal VOCs. We collected and characterized VOCs from co-cultivation assays of Phoma sp. exposed to wild-type C. vaccinii MWU328, and its cviR - mutant using stir bar sorptive extraction and comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (SBSE-GC × GC-TOFMS). We detected 53 VOCs that differ significantly in abundance between microbial cultures and media controls, including four candidate quorum-regulated fungistatic VOCs produced by C. vaccinii. Importantly, the metabolomes of the bacterial-fungal co-cultures were not the sum of the monoculture VOCs, an emergent property of their VOC-mediated interactions. These data suggest semiochemical feedback loops between microbes that have co-evolved for sensing and responding to exogenous VOCs.

6.
Int J Syst Evol Microbiol ; 68(9): 2967-2968, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30028284

RESUMO

Published data on the genome sequences of Chromobacterium pseudoviolaceum LMG 3953T and Chromobacterium violaceum ATCC 12472T suggest that both isolates belong to the same species. Previous 16S rRNA gene sequence comparisons had demonstrated that these species share 99.9 % sequence similarity. Initial investigations of fatty acid patterns and substrate utilization had shown only a few differences between the type strains of both species. Despite the 47.5 % homology by DNA-DNA hybridization studies between these strains, in silico whole genome sequence comparisons have clearly demonstrated that OrthoANIu and Mash/MinHash values were >99.18 %. Molecular phylogeny based on the estimated phylogenetic positions of the published genome sequences of the two type strains, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses indicate that these strains are members of the same species. Due to priority of publication and validation of names, Chromobacterium pseudoviolaceum is reclassified as Chromobacterium violaceum.


Assuntos
Chromobacterium/classificação , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Genome Announc ; 6(15)2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650585

RESUMO

Chromobacterium sp. nov. strains MWU13-2610 and MWU14-2602 were isolated from cranberry bogs in the Cape Cod National Seashore. These nonpigmented bacteria represent two new presumptive species of the rapidly growing genus Chromobacterium Gene homologs are present for multiple antibiotic resistance, virulence functions, and prophages.

8.
J Dent Educ ; 81(5): 526-533, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28461629

RESUMO

Predental students are often unsuccessful in gaining admission to dental school because of low academic scores. Many of these students are from economically and/or educationally disadvantaged backgrounds. Postbaccalaureate and Master's programs provide these students with the opportunity to raise their grade point averages and/or scores on the Dental Admission Test and then apply or reapply for dental school admission. The aim of this study was to compare seven of these postbac programs and their success rates in gaining dental school admission for their graduates. Data were gathered in 2016 from the directors of dedicated predental postbac programs at seven universities in the United States to compare their programs' duration, size of cohort, and percentage of participants gaining admission to dental school and graduating. These predental postbac programs varied in duration, cohort size, and tuition, but had a similar purpose in preparing students for the rigors of dental school. Most of the programs were small, some were selective for disadvantaged students, and all were heavily focused on biological sciences. The dental school admission rate for participants in these seven programs ranged from 45% to over 95%. Students who gained dental school admission after participating in these programs had a 95-100% graduation rate from dental school. These results demonstrate the success of these seven programs in preparing students to gain admission to and graduation from dental school and contribute to diversifying the population of dental students and thus of practicing dentists.


Assuntos
Educação Pré-Odontológica , Grupos Minoritários/educação , Critérios de Admissão Escolar , Logro , Avaliação Educacional , Humanos , Estados Unidos , Populações Vulneráveis
9.
Genome Announc ; 5(12)2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28336604

RESUMO

Chromobacterium pseudoviolaceum LMG 3953T was separated from Chromobacterium violaceum in 2009, but little is known of its origin or environmental role. Here, the genome of LMG 3953T was sequenced to understand the evolution of the genus Chromobacterium It is not clear from this sequence that C. pseudoviolaceum is taxonomically distinct from C. violaceum.

10.
Genome Announc ; 5(12)2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28336605

RESUMO

Chromobacterium subtsugae MWU12-2387 was isolated from the rhizosphere of cranberry plants. While it is unknown what environmental role these bacteria play in bog soils, they hold potential as biological control agents against nematodes and insect pests. Potential virulence genes were identified, including the violacein synthesis pathway, siderophores, and several chitinases.

11.
Genome Announc ; 5(12)2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28336606

RESUMO

Chromobacterium aquaticum CC-SEYA-1T, isolated from a spring in Taiwan, shares many characteristics with other members of the genus but also contains auxin biosynthesis genes and does not produce the pigment violacein. Chromobacterium sp. 49, isolated from Brazil, is identified here as C. aquaticum, indicating that this is a cosmopolitan species.

12.
Genome Announc ; 3(5)2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26358592

RESUMO

Chromobacterium subtsugae was isolated from cranberry bogs in Massachusetts. While it is unknown what environmental role these bacteria play in bog soils, they hold potential as biological control agents against the larvae of insect pests. Potential virulence genes were identified, including the violacein synthesis pathway, siderophores, and several chitinases.

13.
Genome Announc ; 3(3)2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25999572

RESUMO

Chromobacterium vaccinii has been isolated only from cranberry bogs in Massachusetts. While it is unknown what role these bacteria play in their natural environments, they hold potential as biological control agents against the larvae of insect pests. Potential virulence genes were identified, including the violacein synthesis pathway, siderophores, and chitinases.

14.
Int J Syst Evol Microbiol ; 63(Pt 5): 1840-1846, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22984138

RESUMO

A large number of Gram-negative, motile, mesophilic, violacein-producing bacteria were isolated from the soils and roots of Vaccinium macrocarpon Ait. and Kalmia angustifolia L. plants and from irrigation ponds associated with wild and cultivated cranberry bogs in Massachusetts, USA. Phylogenetic analyses of 16S rRNA gene sequences placed these isolates in a clade with Chromobacterium species, but the specialized environment from which they were isolated, their low genomic DNA relatedness with Chromobacterium violaceum ATCC 12472(T) and C. subtsugae PRAA4-1(T), significant differences in fatty acid composition and colony morphology indicate that the cranberry and Kalmia isolates comprise a separate species of Chromobacterium, for which the name Chromobacterium vaccinii sp. nov. is proposed. Strain MWU205(T) ( = ATCC BAA-2314(T)  = DSM 25150(T)) is proposed as the type strain for the novel species. Phenotypic analysis of 26 independent isolates of C. vaccinii sp. nov. indicates that, despite close geographical and biological proximity, there is considerable metabolic diversity among individuals within the population.


Assuntos
Chromobacterium/classificação , Filogenia , Vaccinium macrocarpon/microbiologia , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Chromobacterium/genética , Chromobacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/análise , Indóis/análise , Massachusetts , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Lagoas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Áreas Alagadas
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