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1.
Artigo em Inglês | MEDLINE | ID: mdl-32048984

RESUMO

A Gram-stain-negative, non-motile and rod-shaped bacterium, designated strain 5.0403-2T, was isolated from a cave soil sample collected from Tiandong Cave, Guizhou Province, south-west PR China. Cells showed positive oxidase and catalase reactions. The predominant isoprenoid quinone was MK-7. The major fatty acids were identified as iso-C15 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), iso-C17 : 0 3OH and summed feature 9 (iso-C17 : 1 ω9c or C16 : 0 10-methyl). The cellular polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, three unidentified phosphoglycolipids and four unidentified lipids. The genomic DNA G+C content was 36.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 5.0403-2T should be assigned to the genus Sphingobacterium. Results of 16S rRNA gene sequence similarity analysis showed that strain 5.0403-2T was most similar to Sphingobacterium bovisgrunnientis KCTC 52685T (98.7 %), Sphingobacterium composti KCTC 12578T (98.0 %) and Sphingobacterium alimentarium DSM 22362T (97.3 %) and less than 95.0 % similar to other species of the genus Sphingobacterium. The average nucleotide identity values between strain 5.0403-2T and S. bovisgrunnientis KCTC 52685T, S. composti KCTC 12578T and S. alimentarium DSM 22362T were 94.2, 82.3 and 77.2 % respectively. The digitalDNA-DNA hybridization values between strain 5.0403-2T and S. bovisgrunnientis KCTC 52685T, S. composti KCTC 12578T and S. alimentarium DSM 22362T were 68.4, 25.6 and 20.7 %. These results indicated that the isolate represented a novel genomic species. The polyphasic taxonomic characteristics indicated that strain 5.0304-2T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium cavernae sp. nov. (type strain 5.0403-2T=KCTC 62981T=CCTCC AB 2019257T) is proposed.

2.
Int J Syst Evol Microbiol ; 70(1): 687-692, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31778348

RESUMO

A Gram-stain negative, aerobic, motile and rod-shaped bacterium, designated strain 3.1105T, was isolated from a karst district soil sample collected from Tiandong cave, Guizhou province, south-west PR China. The isolate grew at 10-40 °C and pH 5.0-8.0 and tolerated up to 1 % NaCl (w/v) on R2A medium, with optimal growth at 25-30 °C, pH 7.0 and 0 % NaCl (w/v). Cells showed oxidase-positive and catalase-positive reactions. The respiratory quinone was Q-10. The predominant cellular fatty acids contained C18 : 1ω7c 11-methyl, summed feature 8 (C18 : 1ω7c or C18 : 1ω6c), C16 : 0 and C17 : 0. The major polar lipids were phosphatidylglycerol and monoglycosyldiglycerides. The genomic DNA G+C content was 56.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that 3.1105T should be affiliated to the genus Asticcacaulis and showed highest 16S rRNA gene sequence similarity values with Asticcacaulis excentricus CB 48T (96.0 %), Asticcacaulis endophyticus ZFGT-14T (95.3 %) and lower than 95.3 % similarity to other species of the genus Asticcacaulis. The polyphasic taxonomic characteristics indicated that strain 3.1105T represents a novel species of the genus Asticcacaulis, for which the name Asticcacaulis tiandongensis sp. nov., (type strain 3.1105T=KCTC 62978T=CCTCC AB 2018268T) is proposed.


Assuntos
Caulobacteraceae/classificação , Cavernas/microbiologia , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Caulobacteraceae/isolamento & purificação , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
3.
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
4.
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
5.
J Antibiot (Tokyo) ; 72(10): 752-758, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31324892

RESUMO

Two new diketopiperazines (1, 2), one new polyprenol (3), together with 19 known compounds (4-22) were obtained from the EtOAc extract of Bionectria sp. Y1085, an endophytic fungus isolated from the plant Huperzia serrata. Their structures were elucidated by extensive NMR and MS analysis. Bionectin D (1) is a rare diketopiperazine with a single methylthio substitution at the α-carbon of cyclized amino acid residue. The antibacterial activity of compounds was assayed against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium ATCC 6539, and some metabolites (1, 2, 10, 11, and 14) exhibited evident antibacterial activity.


Assuntos
Antibacterianos/isolamento & purificação , Dicetopiperazinas/isolamento & purificação , Endófitos/química , Hypocreales/química , Antibacterianos/química , Antibacterianos/farmacologia , Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Endófitos/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Huperzia/microbiologia , Hypocreales/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
6.
Int J Syst Evol Microbiol ; 69(7): 2082-2088, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31099732

RESUMO

A Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium, designated strain X7XT, was isolated from a rhizosphere soil sample of Nicotiana tabacum L. collected from a tobacco factory located in Kunming, south-western China. The cells showed oxidase-positive and catalase-positive reactions. Growth occurred at 20-40 °C and pH 6.0-8.0, with optimal growth at 30 °C and pH 7.0. The predominant respiratory quinone was MK-7. The major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 3OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c). The cellular polar lipids contained phosphatidylethanolamine, an unidentified aminophospholipid, two unidentified glycolipids, four unidentified aminolipids and four unidentified lipids. The genomic DNA G+C content was 49.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain X7XT should be affiliated to the genus Flavisolibacter. Results from further analysis showed that strain X7XT had highest 16S rRNA gene sequence similarity to Flavisolibacter metallilatus TX0661T (96.4 %) and 'Flavisolibacter swuensis' SR2-4-2T (96.4 %), followed by other species of the genus Flavisolibacter. The polyphasic taxonomic characteristics indicated that strain X7XT represents a novel species of the genus Flavisolibacter, for which the name Flavisolibacternicotianae sp. nov. (type strain X7XT=KCTC 62326T=CGMCC 16451T) is proposed.


Assuntos
Bacteroidetes/classificação , Filogenia , Rizosfera , Microbiologia do Solo , Tabaco/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
7.
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
8.
Int J Syst Evol Microbiol ; 68(8): 2574-2579, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29944093

RESUMO

A Gram-staining-negative, aerobic, motile and rod-shaped bacterium, designated strain X1-8T, was isolated from rhizosphere soil of Nicotiana tabacum L. collected from the tobacco produce base located in Kunming, south-west PR China. Cells showed oxidase-negative and catalase-positive reactions and were motile by means of peritrichous flagella. Growth occurred at 25-40 °C and pH 6.0-8.0 with optimal growth at 30-35 °C, pH 7.0. The major respiratory lipoquinone was Q-10. C16 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) were identified as major cellular fatty acids. The profile of polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, sphingoglycolipid, phosphatidylcholine and one unidentified glycolipid. The major polyamine was sym-homospermidine. The genomic DNA G+C content was 66.5 mol%. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that X1-8T should be affiliated to the genus Sphingomonasand formed a clade with most closely related species Sphingomonas changbaiensisNBRC 104936T. The results of 16S rRNA gene sequences similarity analysis indicated that X1-8T had the highest similarity with S. changbaiensisNBRC 104936T (98.4 %) and lower than 96.0 % with other species of the genus Sphingomonas. DNA-DNA hybridization data indicated that X1-8T represented a novel genomic species of the genus Sphingomonas. The characteristics determined in the polyphasic taxonomic study indicated that X1-8T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas tabacisoli sp. nov. (type strain X1-8T=KCTC 62032T=CGMCC 1.16275T) is proposed.


Assuntos
Filogenia , Rizosfera , Microbiologia do Solo , Sphingomonas/classificação , Tabaco/microbiologia , 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 , Espermidina/análogos & derivados , Espermidina/química , Sphingomonas/genética , Sphingomonas/isolamento & purificação , Ubiquinona/química
9.
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
10.
Antonie Van Leeuwenhoek ; 111(7): 1237-1257, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29397489

RESUMO

Accumulated evidence suggests that root exudates have a major role in mediating plant-microbe interactions in the rhizosphere. Here, we characterized tobacco root exudates (TREs) by GC-MS and nicotine, scopoletin, and octadecane were identified as three main components of TREs. Qualitative and quantitative chemotaxis assays revealed that Pseudomonas aeruginosa NXHG29 with antagonistic activity displayed positive chemotactic responses towards TREs and their three main components (nicotine, scopoletin, octadecane) and its enhanced chemotaxis were induced by these substances in a concentration-dependent manner. Furthermore, following GC-MS and chemotaxis analysis, nicotine was selected as the target for evaluation of the effect on NXHG29 regarding antagonism, growth, root colonization and biocontrol efficiency. Results of in vitro studies showed that nicotine as a sole carbon source could enhance growth of NXHG29 and significantly increased the antagonism of NXHG29. We also demonstrated that nicotine exerted enhancing effects on the colonization ability of NXHG29 on tobacco roots by combining CLSM observations with investigation of population level dynamics by selective dilution plating method. Results from greenhouse experiments suggested nicotine exhibited stimulatory effects on the biocontrol efficiency of NXHG29 against bacterial wilt and black shank on tobacco. The stimulatory effect of nicotine was affected by the concentration and timing of nicotine application and further supported by the results of population level of NXHG29 on tobacco roots. This is the first report on the enhancement effect of nicotine from TREs on an antagonistic bacterium for its root colonization, control of soil-borne pathogens, regarding the chemotaxis and in vitro antagonism and growth.


Assuntos
Quimiotaxia/efeitos dos fármacos , Nicotina/farmacologia , Exsudatos de Plantas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Tabaco/química , Cromatografia Gasosa-Espectrometria de Massas , Nicotina/química , Nicotina/isolamento & purificação , Doenças das Plantas/microbiologia , Exsudatos de Plantas/química , Exsudatos de Plantas/isolamento & purificação , Raízes de Plantas/química , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/fisiologia
11.
J Proteomics ; 177: 31-39, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29425737

RESUMO

Bacillus nematocida B16 (B16) is a pathogenic bacterium that is nematotoxic to plant-parasitic nematodes. In this study, we performed a quantitative lysine acetylome analysis on B16 to understand the potential roles of protein lysine acetylation on this host-pathogen interaction. Altogether, we identified 529 acetylation sites in 349 proteins, quantified 411 sites in 288 proteins, determined that the acetylation levels of 18 sites were up-regulated and those of 19 sites were down-regulated during pathogenesis. The acetylated proteins mainly participated in metabolic processes, protein synthesis, and cell wall/membrane biogenesis. Moreover, these proteins are involved in more than twenty KEGG pathways. Eight peptide motifs of acetylated proteins were identified, five of which have been thus far found only in the B16 acetylome. Twenty-two acetylated proteins were found to be involved in the synthesis of nematode attractants, and two were found to be involved in the secretion of virulence factors. In addition, the acetylation levels of ten lysine sites were regulated significantly differently in the presence of nematodes. Our results reveal that lysine acetylation may play roles in regulating B16-nematode interaction. SIGNIFICANCE: B. nematocida B16 is a bio-control bacterium against nematodes. It lures nematodes to their death by a Trojan horse mechanism. But there is little understanding about the regulation of this "Trojan horse" like pathogenesis. Lysine acetylation was reported to regulate diverse cellular processes. Our results revealed that lysine acetylation played indeed roles in regulating the B16-nematodes interaction. Our data laid a foundation for studying the molecule mechanism of lysine acetylation in regulating this host-pathogen interaction.


Assuntos
Bacillus/patogenicidade , Interações Hospedeiro-Patógeno , Lisina/metabolismo , Nematoides/microbiologia , Acetilação , Animais , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
12.
Int J Syst Evol Microbiol ; 67(11): 4808-4813, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28984223

RESUMO

A Gram-staining-negative, non-motile and rod-shaped bacterium, designated strain h337T, was isolated from an arable soil sample of a tobacco field in Kunming, south-west China. The cells showed oxidase-positive and catalase-positive reactions. Growth was observed at 10-35 °C, at pH 6.0-9.0 and in the presence of up to 3 % (w/v) NaCl, with optimal growth at 30 °C, pH 7.0 and with 1-2 % (w/v) NaCl. The predominant isoprenoid quinone was MK-7. The major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 3-OH, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B). The cellular polar lipids contained phosphatidylethanolamine, sphingophospholipid, four unidentified phospholipids, five unidentified lipids and three unidentified aminophospholipids. The genomic DNA G+C content was 41.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain h337T should be assigned to the genus Sphingobacterium. 16S rRNA gene sequence similarity analysis showed that strain h337T was most closely related to 'Sphingobacteriumyamdrokense' 3-0-1 (98.8 %) and Sphingobacteriumyanglingense CCNWSP36-1T (98.5 %) and shared less than 97 % similarity with other species of the genus Sphingobacterium. DNA-DNA hybridization data indicated that the isolate represented a novel genomic species belonging to the genus Sphingobacterium. The characteristics determined in this polyphasic taxonomic study indicated that strain h337T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium tabacisoli sp. nov. (type strain h337T=KCTC 52298T=CCTCC AB 2017155T) is proposed.


Assuntos
Filogenia , Microbiologia do Solo , Sphingobacterium/classificação , Tabaco/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/genética , Sphingobacterium/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
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
14.
Genes (Basel) ; 7(10)2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27775569

RESUMO

The vast majority of lepidopterans, about 90%, are moths. Some moths, particularly their caterpillars, are major agricultural and forestry pests in many parts of the world. However, some other members of moths, such as the silkworm Bombyx mori, are famous for their economic value. Fire et al. in 1998 initially found that exogenous double-stranded RNA (dsRNA) can silence the homolog endogenous mRNA in organisms, which is called RNA interference (RNAi). Soon after, the RNAi technique proved to be very promising not only in gene function determination but also in pest control. However, later studies demonstrate that performing RNAi in moths is not as straightforward as shown in other insect taxa. Nevertheless, since 2007, especially after 2010, an increasing number of reports have been published that describe successful RNAi experiments in different moth species either on gene function analysis or on pest management exploration. So far, more than 100 peer-reviewed papers have reported successful RNAi experiments in moths, covering 10 families and 25 species. By using classic and novel dsRNA delivery methods, these studies effectively silence the expression of various target genes and determine their function in larval development, reproduction, immunology, resistance against chemicals, and other biological processes. In addition, a number of laboratory and field trials have demonstrated that RNAi is also a potential strategy for moth pest management. In this review, therefore, we summarize and discuss the mechanisms and applications of the RNAi technique in moths by focusing on recent progresses.

15.
Phytother Res ; 30(10): 1572-1583, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27373780

RESUMO

The entomopathogenic fungus Ophiocordyceps sinensis, formerly known as Cordyceps sinensis, has long been used as a traditional Chinese medicine for the treatment of many illnesses. In recent years its usage has increased dramatically because of the improvement of people's living standard and the emphasis on health. Such demands have resulted in over-harvesting of this fungus in the wild. Fortunately, scientists have demonstrated that artificially cultured and fermented mycelial products of O. sinensis have similar pharmacological activities to wild O. sinensis. The availability of laboratory cultures will likely to further expand its usage for the treatment of various illnesses. In this review, we summarize recent results on the pharmacological activities of the components of O. sinensis and their putative mechanisms of actions. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Cordyceps/química , Medicina Tradicional Chinesa/métodos
16.
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
17.
Bioprocess Biosyst Eng ; 38(2): 399-405, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25218329

RESUMO

This study aimed to improve the production of polysaccharide by engineering the biosynthetic pathway in Ganoderma lucidum through the overexpression of α-phosphoglucomutase (PGM) gene. PGM is responsible for the linkage between sugar catabolism and sugar anabolism. The effects of PGM gene overexpression on intracellular polysaccharide (IPS) content, extracellular polysaccharide (EPS) production and transcription levels of three genes encoding the enzymes involved in polysaccharide biosynthesis, including PGM, UDP-glucose pyrophosphorylase (UGP), and ß-1,3-glucan synthase (GLS), were investigated. The maximum IPS content and EPS production in G. lucidum overexpressing the PGM gene were 23.67 mg/100 mg dry weight and 1.76 g/L, respectively, which were higher by 40.5 and 44.3% than those of the wild-type strain. The transcription levels of PGM, UGP and GLS were upregulated by 4.77-, 1.51- and 1.53-fold, respectively, in the engineered strain, suggesting that increased polysaccharide biosynthesis may result from a higher expression of those genes.


Assuntos
Reatores Biológicos/microbiologia , Genes Sintéticos/genética , Melhoramento Genético/métodos , Fosfoglucomutase/fisiologia , Polissacarídeos/biossíntese , Reishi/fisiologia , Recombinação Homóloga/genética , Polissacarídeos/genética , Polissacarídeos/isolamento & purificação , Regulação para Cima/genética
18.
J Microbiol ; 51(3): 289-94, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23812807

RESUMO

A Gram-positive, catalase- and oxidase-positive, strictly aerobic, endospore-forming rod bacterium, designated K3514(T), was isolated from the leaves of Nicotiana tabacum. The strain was able to grow at temperatures of 8-40°C, pH 5.0-10.0 and NaCl concentrations of 0-7%. The predominant quinones (>30%) of this strain were MK-7(H2) and MK-7. Phylogenetic analysis of 16S rRNA gene sequence showed that strain K3514(T) was affiliated to the genus Lysinibacillus, with its closest relatives being Lysinibacillus mangiferihumi (98.3% sequence similarity), Lysinibacillus sphaericus (97.9% sequence similarity), Lysinibacillus fusiformis (97.4% sequence similarity), and Lysinibacillus xylanilyticus (97.3% sequence similarity). However, low levels of DNA-DNA relatedness values suggested that the isolate was distinct from the other closest Lysinibacillus species. Additionally, based on analysis of morphological, physiological, and biochemical characteristics, the isolate could be differentiated from the closest known relatives. Therefore, based on polyphasic taxonomic data, the novel isolate likely represents a novel species, for which the name Lysinibacillus tabacifolii sp. nov. and the type strain K3514(T) (=KCTC 33042(T) =CCTCC AB 2012050(T)) are proposed.


Assuntos
Bacillaceae/genética , Folhas de Planta/microbiologia , Tabaco/microbiologia , Bacillaceae/classificação , Genes de RNAr/genética , Filogenia
19.
Antonie Van Leeuwenhoek ; 103(2): 299-312, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22987248

RESUMO

Endophytes play an important role in protection of host plants from infection by phytopathogens. Endophytic bacteria were isolated from five different parts (root, stem, petiole, leaf and seed) of Panax notoginseng and evaluated for antagonistic activity against Fusarium oxysporum, Ralstonia sp. and Meloidogyne hapla, three major pathogens associated with root-rot disease complex of P. notoginseng. From 1000 endophytic bacterial strains evaluated in vitro, 104 strains exhibited antagonistic properties against at least one of these three pathogens. Phylogenetic analyses of their 16S rRNA gene sequences showed that these 104 antagonistic bacteria belong to four clusters: Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes/Chlorobi. Members of the Firmicutes, in particular the Bacillus spp., were predominant in all analyzed tissues. The root was the main reservoir for antagonistic bacteria. Of the 104 antagonists, 51 strains showed antagonistic activities to one pathogen only, while 43 and 10 displayed the activities towards two and all three pathogens, respectively. The most dominant species in all tissues were Bacillus amyloliquefaciens subsp. plantarum and Bacillus methylotrophicus, which were represented by eight strains with broad antagonistic spectrum to the all three test pathogens of root-rot disease complex of P. notoginseng.


Assuntos
Antibiose , Bactérias/classificação , Fenômenos Fisiológicos Bacterianos , Fusarium/crescimento & desenvolvimento , Panax notoginseng/microbiologia , Ralstonia/crescimento & desenvolvimento , Tylenchoidea/crescimento & desenvolvimento , Animais , Bactérias/isolamento & purificação , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Endófitos/classificação , Endófitos/isolamento & purificação , Endófitos/fisiologia , Dados de Sequência Molecular , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
Ying Yong Sheng Tai Xue Bao ; 23(7): 1985-91, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23173478

RESUMO

Phosphate-solubilizing bacteria (PSB) were isolated from 100 soil samples collected from a phosphorous-rich area around the Dianchi Lake of Yunnan Province, Southwest China. The chemotatic PSB strains were screened by cheA gene detection, and their chemotaxis was verified by the method of soft agar plate. The tricalcium phosphate (TCP)-solubilizing activities of PSB were determined with molybdenum blue spectrophotometry. Based on 16S rRNA sequences, the phylogenic relationships of the PSB were analyzed. A total of 145 PSB strains with a diameter of phosphate-solubilizing halo zone ranged from 0.5 cm to 2 cm were isolated, among which, 37 strains were chemotactic. The 37 chemotactic strains showed chemotaxis towards four test attractants, and exhibited TCP-solubilizing activity. Phylogenic analysis revealed that the 37 chemotatic strains were belonged to 17 species of 10 genera, in which, Pseudomonas was dominant (9 strains of 5 species), followed by Enterobacter (8 strains of 3 species). Only one species (Bacillus aryabhattai) was isolated from Bacillus, but 9 strains were identified.


Assuntos
Bactérias/metabolismo , Biodiversidade , Fosfatos/química , Fosfatos/metabolismo , Microbiologia do Solo , Bactérias/isolamento & purificação , China , Enterobacter/isolamento & purificação , Enterobacter/metabolismo , Lagos , Filogenia , Pseudomonas/isolamento & purificação , Pseudomonas/metabolismo , Solo/química
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