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1.
Int J Syst Evol Microbiol ; 70(1): 604-610, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31697229

RESUMO

A Gram-stain-negative, yellow-green bacterium, designated 1.1416T, was isolated from wormcast of Eisenia foetida. The strain was non-motile, rod-shaped, and grew optimally on NA medium at 30 °C, pH 7.0 and with 0 % (w/v) NaCl. On the basis of the 16S rRNA gene sequence and phylogenetic analysis, 1.1416T showed the highest degree of 16S rRNA gene sequence similarity to Luteimonas arsenica 26-35T (96.2 %), followed by Luteimonas lutimaris G3T (96.1 %). The respiratory quinone of 1.1416T was ubiquinone-8 (Q-8), and its major cellular fatty acids were iso-C15 : 0 (39.8 %), summed feature 9 (iso-C17 : 1 ω9c or C16 : 0 10-methyl) (18.6 %). The major polar lipids of 1.1416T were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and six unidentified phospholipids. The genomic DNA G+C content of 1.1416T was 71.0 mol%. According to the results of the phenotypic and chemotaxonomic phylogenetic analyses, strain 1.1416T represents a novel species of the genus Luteimonas, for which the name Luteimonas lumbrici sp. nov. is proposed, with strain 1.1416T (=KCTC 62979T=CCTCC AB 2018348T) as the type strain.


Assuntos
Oligoquetos/microbiologia , Filogenia , Xanthomonadaceae/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química , Xanthomonadaceae/isolamento & purificação
2.
Int J Syst Evol Microbiol ; 69(12): 3716-3722, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31592754

RESUMO

A Gram-stain-negative, rod-shaped, non-motile, aerobic, catalase-negative and oxidase-positive bacterium, designated strain Sn-9-2T, was isolated from a cave soil sample collected from Tiandong cave, Guizhou Province, south-west PR China. Growth occurred at 15-40 °C (optimum, 30 °C), at pH 5.0-9.0 (optimum, pH 7.0-8.0) and with 0-1 % NaCl (w/v). The predominant respiration quinone was ubiquinone-10 (Q-10). The major cellular fatty acids were summed feature 8 (C18 : 1ω7c or C18 : 1ω6c; 83.9 %) and C16 : 0 (5.8 %). The major polar lipids were phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine, phosphatidylglycerol, three unidentified phospholipids, two unidentified glycolipids, two unidentified polar lipids and one unidentified aminolipid. The DNA G+C content of strain Sn-9-2T was 67.5 mol%. Based on the results of 16S rRNA gene sequence analysis, the nearest phylogenetic neighbours of strain Sn-9-2T (MF958452) were identified as Aquabacter spiritensis (FR733686) DSM 9035T (97.5 %), Xanthobacter autorophicus (jgi.1053054) DSM 432T (97.2 %) and Xanthobacter tagetidis ATCC 700314T RCTF01000015 (96.9 %). The average nucleotide identity values were 78.0, 77.4 and 77.6 % and the digital DNA-DNA hybridization values were 21.8, 22.0 and 18.8 % between strain Sn-9-2T and A. spiritensis DSM 9035T, X. autotrophicus DSM 432T and X. tagetidis DSM 11105T, respectively. The DNA-DNA hybridization data indicated that strain Sn-9-2T represented a novel genomic species. On the basis of the results of phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain Sn-9-2T should represent a novel species of the genus Aquabacter, for which the name Aquabactercavernae sp. nov. is proposed. The type strain is Sn-9-2T (=KCTC 62308T=CCTCC AB 2018270T).


Assuntos
Alphaproteobacteria/classificação , Cavernas/microbiologia , Filogenia , Microbiologia do Solo , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
3.
J Proteomics ; 192: 358-365, 2019 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-30282050

RESUMO

Soil fungistasis limits the effect of fungal agents designed to control plant-parasitic nematodes. Benzaldehyde is a fungistatic factor produced by soil microorganisms that can suppress conidial germination, but the molecular mechanism of this suppression is unknown. In this study, three conidial proteomes of Arthrobotrys oligospora ATCC24927, a nematode-trapping fungus, were obtained, quantified, and compared. Under benzaldehyde fungistatic stress, conidial protein expression profile changed significantly. Screening with a twofold selection criterion revealed 164 up-regulated and 110 down-regulated proteins. 17 proteins related to protein translation were down-regulated and gene transcription analysis suggested that the repression of proteins translation might be one mechanism by which benzaldehyde inhibites conidial germination. Benzaldehyde also resulted in the down-regulation of respiratory chain proteins and mitochondrial processes, as well as the repression of conidial DNA synthesis. In addition, the conidia up-regulated several proteins that enable it to resist benzaldehyde-induced fungistatis, and this was confirmed by a functional assessment of two knockout mutants. This study reveals putative mechanisms by which benzaldehyde causes fungistasis as well as the proteomic response of conidia to benzaldehyde. SIGNIFICANCE: Soil fungistasis limits the effect of fungal agents designed to control plant-parasitic nematodes. Benzaldehyde is one of fungistatic factors produced by soil microorganisms that can suppress conidial germination. In this study, we found that conidial protein expression profile changed significantly under benzaldehyde fungistatic stress. This research revealed new mechanistic data that describe how benzaldehyde is responsible for fungiststis by inhibiting conidial germination. Moreover, we also found that conidia can resist benzaldehyde by up-regulating proteins such as benzaldehyde dehydrogenase and heat shock proteins. This study also showed that proteomics methods play important roles in addressing soil fungistatic mechanisms.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/fisiologia , Benzaldeídos/farmacologia , Proteínas Fúngicas/metabolismo , Proteoma/metabolismo , Esporos Fúngicos/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos
4.
Int J Biochem Cell Biol ; 98: 104-112, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29544894

RESUMO

Ammonia is one of the fungistatic factors in soil that can suppress conidial germination, but the molecular mechanism underlying the suppression is unknown. In this study, the proteomes of fungistatic conidia, fresh conidia and germinated conidia of Arthrobotrys oligospora ATCC24927 were determined and quantified. The protein expression profile of fungistatic conidia was significantly different from those in the other two conditions. 281 proteins were down expressed in fungistatic conidia and characterized by GO annotation. Gene transcription analysis and inhibition of puromycin (a protein translation inhibitor) on conidial germination suggested that down expression of 33 protein translation related proteins might well result in repression of protein synthesis and inhibition of conidial germination. In addition, 16 down-expressed proteins were mapped to the Ras/mitogen-activated protein (Ras/MAP) regulatory networks which regulate conidial DNA synthesis. The conidial DNA synthesis was found to be definitely inhibited under by ammonia, and function studies of two Ras/MAP proteins by using knock-out strains provided partial evidence that Ras/MAP pathway regulate the conidial germination. These results suggested that down-expression of Ras/MAP related proteins might result in inhibition of DNA synthesis and finally result in inhibition conidial germination. This study revealed partial fungistatic mechanism of ammonia against conidial germination.


Assuntos
Amônia/farmacologia , Ascomicetos/fisiologia , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Nematoides/microbiologia , Proteômica/métodos , Esporos Fúngicos/crescimento & desenvolvimento , Animais , Proteoma , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/metabolismo
5.
Int J Syst Evol Microbiol ; 67(10): 3699-3705, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28879837

RESUMO

A Gram-stain-positive, rod-shaped, motile bacterium, designated as 1404T, was isolated from leaves of Chinese red pepper (Huajiao) (Zanthoxylum bungeanum Maxim) collected from Gansu, north-west China. Spores were not observed under a range of conditions. Strain 1404T was observed to grow at 15-45 °C and pH 6.0-10.0 and in presence of 0-5 % (w/v) NaCl concentration. The cell wall of strain 1404T was found to contain meso-diaminopimelic acid, and the predominant respiratory quinone was identified as MK-7. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid as well as three unidentified polar lipids. The major fatty acids profile of strain 1404T consisted of iso-C15 : 0 (25.6 %), anteiso-C15 : 0 (18.4 %) and iso-C14 : 0 (12.1 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 1404T was affiliated to the genus Bacillus and was closely related to Bacillusoryzisoli 1DS3-10T, Bacillusbenzoevorans DSM 5391T and Bacilluscirculans DSM 11T with sequence similarity of 98.3, 98.2 and 96.9 %, respectively. The G+C content of the genomic DNA was determined to be 39.4 mol%. DNA-DNA hybridization values indicated that relatedness between strain 1404T and the type strains of closely related species of the genus Bacillus was below 41 %. Therefore, on the basis of the data from the polyphasic taxonomic study presented, strain 1404T represents a novel species of the genus Bacillus, for which the name proposed is Bacillus endozanthoxylicus sp. nov. The type strain is 1404T (=CCTCC AB 2017021T=KCTC 33827T).


Assuntos
Bacillus/classificação , Filogenia , Folhas de Planta/microbiologia , Zanthoxylum/microbiologia , Bacillus/genética , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfatidilgliceróis/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
J Mech Behav Biomed Mater ; 57: 269-79, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26741534

RESUMO

The measurement uncertainty of strains has been assessed in a bone analogue (sawbone), bovine trabecular bone and bone-cement interface specimens under zero load using the Digital Volume Correlation (DVC) method. The effects of sub-volume size, sample constraint and preload on the measured strain uncertainty have been examined. There is generally a trade-off between the measurement uncertainty and the spatial resolution. Suitable sub-volume sizes have been be selected based on a compromise between the measurement uncertainty and the spatial resolution of the cases considered. A ratio of sub-volume size to a microstructure characteristic (Tb.Sp) was introduced to reflect a suitable spatial resolution, and the measurement uncertainty associated was assessed. Specifically, ratios between 1.6 and 4 appear to give rise to standard deviations in the measured strains between 166 and 620 µÎµ in all the cases considered, which would seem to suffice for strain analysis in pre as well as post yield loading regimes. A microscale finite element (µFE) model was built from the CT images of the sawbone, and the results from the µFE model and a continuum FE model were compared with those from the DVC. The strain results were found to differ significantly between the two methods at tissue level, consistent in trend with the results found in human bones, indicating mainly a limitation of the current DVC method in mapping strains at this level.


Assuntos
Cimentos para Ossos , Osso e Ossos , Estresse Mecânico , Incerteza , Animais , Osso e Ossos/diagnóstico por imagem , Bovinos , Força Compressiva , Análise de Elementos Finitos , Humanos , Coelhos , Microtomografia por Raio-X
7.
Pest Manag Sci ; 71(3): 415-22, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24799254

RESUMO

BACKGROUND: The use of dually antagonistic bacteria (DAB) as alternatives to chemicals for biological control of disease complexes has received little attention. In this study targeting the Meloidogyne incognita-Phytophthora nicotianae complex, DAB from the tobacco rhizosphere were identified and screened against the diseases caused by one or both pathogens in tobacco. RESULTS: From 450 soil tobacco rhizosphere samples, 26 DAB were identified and had in vitro nematicidal and antifungal efficacies of 37.2-100% and 32.9-73.4% respectively. These DAB were classified into 19 species of 11 genera. In pot experiments, Streptomyces flavofungini SNA26, Pseudomonas putida SNB53 and Serratia marcescens subsp. sakuensis SNB54 effectively suppressed black shank (control effect 72.0-80.2%), root knot (70.0-81.7) and the disease complex (58.7-68.5%) caused by P. nicotianae, M. incognita and both pathogens in tobacco respectively. CONCLUSION: Nineteen DAB species were demonstrated to be antagonists against the M. incognita-P. nicotianae complex. Because S. flavofungini SNA26, P. putida SNB53 and S. marcescens subsp. sakuensis SNB54 significantly suppressed the infection of M. incognita and P. nicotianae in tobacco, these species have potential for development as biocontrol agents against the diseases and complex caused by these two pathogens.


Assuntos
Ascomicetos/fisiologia , Phytophthora/fisiologia , Tabaco/microbiologia , Tabaco/parasitologia , Tylenchoidea/fisiologia , Animais , Antibiose , Bactérias/classificação , Bactérias/isolamento & purificação , Agentes de Controle Biológico , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Rizosfera , Microbiologia do Solo
8.
Curr Microbiol ; 64(5): 449-56, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22349956

RESUMO

Members of group III histidine kinases from different filamentous fungi were previously shown to mediate osmoregulation and resistance to dicarboximide, phenylpyrrole and, aromatic hydrocarbon fungicides. In this study, we report the disruption of the gene encoding group III histidine kinase, AlHK1, in the economically important plant pathogen Alternaria longipes. The AlHK1 gene disruption had pleiotropic effects on this fungus. Besides the expected osmosensitivity and fungicides resistance, AlHK1 participated in the spore production process. In addition, the ΔAlHK1 strains had stronger aggressive ability to infect their host plant than that of their parental strain, the wild-type strain C-00, suggested that AlHK1 was involved in the pathogenicity of A. longipes and performed in this function by a negative manner. This is the first report to our knowledge.


Assuntos
Alternaria/enzimologia , Alternaria/patogenicidade , Proteínas Fúngicas/metabolismo , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Proteínas Quinases/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Equilíbrio Hidroeletrolítico , Alternaria/efeitos dos fármacos , Alternaria/crescimento & desenvolvimento , Regulação para Baixo , Farmacorresistência Fúngica , Proteínas Fúngicas/genética , Histidina Quinase , Dados de Sequência Molecular , Osmose , Proteínas Quinases/genética , Esporos Fúngicos/enzimologia , Esporos Fúngicos/patogenicidade , Tabaco/microbiologia
10.
Mycopathologia ; 161(5): 307-16, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16649080

RESUMO

The strain ZK7 of Pochonia chlamydosporia var. chlamydosporia and IPC of Paecilomyces lilacinus are highly effective in the biological control against root-knot nematodes infecting tobacco. When applied, they require a specific monitoring method to evaluate the colonization and dispersal in soil. In this work, the randomly amplified polymorphic DNA (RAPD) technique was used to differentiate between the two individual strains and 95 other isolates, including isolates of the same species and common soil fungi. This approach allowed the selection of specific fragments of 1.2 kb (Vc1200) and 2.0 kb (Vc2000) specific for ZK7, 1.4 kb (P1400) and 0.85 kb (P850) specific for IPC, using the random Primers OPL-02, OPD-05, OPD-05 and OPC-11, respectively. These fragments were cloned, sequenced, and used to design sequence-characterized amplification region (SCAR) primers specific for the two strains. In classical polymerase chain reaction (PCR), with serial dilution of ZK7 and IPC pure culture DNAs template, the detection limits of these oligonucleotide SCAR-PCR primers were found to be 10, 1000, 500, 100 pg, respectively. In the dot blotting, digoxigenin (DIG)-labeled amplicons from these four primers specifically recognized the corresponding fragments in the DNAs template of these two strains. The detection limit of these amplicons were 0.2, 0.2, 0.5, 0.5 mug, respectively.


Assuntos
Infecções por Nematoides/prevenção & controle , Paecilomyces/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Doenças das Plantas/parasitologia , Tabaco , DNA Fúngico/química , DNA Fúngico/genética , Paecilomyces/genética , Raízes de Plantas/parasitologia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA
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