To improve antagonistic metabolites production of Bacillus subtilis strain BS501a, physical parameters of fermentation and metal inorganic salts in medium, namely initial pH value, culture temperature, fermentation ti...To improve antagonistic metabolites production of Bacillus subtilis strain BS501a, physical parameters of fermentation and metal inorganic salts in medium, namely initial pH value, culture temperature, fermentation time, concentrations of CaC12, FeSO4, ZnSO4, MnSO4 and MgSO4, were optimized using one-factor-at-a-time and orthogonal tests. The results show that the optimal physical parameters of fermentation are an initial pH of 7.0, a culture temperature of 30 ~C, and a fermentation time of 48 h. The optimal concentrations of metal inorganic salts in basal medium are 10.2 mmol/L CaCl2, 0.4 mmol/L FeSO4, 3.5 mmol/L ZnSO4, 0.6 mmol/L MnSO4 and 2.0 mmol/L MgSO4. Among the metal inorganic salts, MgSO4 and MnSO4 play important roles in the improvement of the antagonistic metabolites production of B. subtilis strain BS501a; especially, MgSO4 contributes a highly significant effect. The average diameter of inhibition zone of the BS501a filtered fermentation supernatant （FFS） cultured in the optimal fermentation conditions against Magnaporthe grisea DWBJ329 reaches 71.4 mm, and there is 2.4-fold increase in antifungal activity as compared with 21.2 mm under the pre-optimized conditions.展开更多
Background:In our previous study,a strain EBS03 with good biocontrol potential was screened out of 48 strains of cotton endophyte Bacillus subtilis by evaluating the controlling effect against cotton Verticillium wilt...Background:In our previous study,a strain EBS03 with good biocontrol potential was screened out of 48 strains of cotton endophyte Bacillus subtilis by evaluating the controlling effect against cotton Verticillium wilt.However,its mechanism for controlling Verticillium wilt remains unclear.The objective of this study was to further clarify its con-trolling effect and mechanism against cotton Verticillium wilt.Results:The results of confrontation culture test and double buckle culture test showed that the inhibitory effects of EBS03 volatile and nonvolatile metabolite on mycelium growth of Verticillium dahliae were 70.03%and 59.00%,respectively;the inhibitory effects of sporulation and microsclerotia germination were 47.16%and 70.06%,respec-tively.In the greenhouse test,the EBS03 fermentation broth root irrigation had the highest controlling effect at 87.11%on cotton Verticillium wilt,and significantly promoted the growth of cotton seedlings.In the field experi-ment,the controlling effect of EBS03 fermentation broth to cotton Verticillium wilt was 42.54%at 60 days after cotton sowing,and the boll number per plant and boll weight in EBS03 fermentation broth seed soaking,root irrigation,and spraying treatments significantly increased by 19.48%and 7.42%,30.90%and 2.62%,15.99%and 9.20%,respec-tively.Furthermore,EBS03 improved the resistance of cotton leaves against the infection of V.dahliae,and induced the outbreak of reactive oxygen species and accumulation of callose.In addition,the results of real time fluorescent quantitative polymerase chain reaction(RT-qPCR)detection showed that EBS03 significantly induced upregulation expression level of defense-related genes PAL,POD,PPO,and PR10 in cotton leaves,enhanced cotton plant resistance to V.dahliae,and inhibited colonization level of this fungal pathogen in cotton.Conclusion:Bacillus subtilis EBS03 has a good biological defense capability,which can inhibit the growth and coloni-zation level of V.dahliae,and activate the resistance of cotton to Verticillium wilt,thus increase cotton yield.展开更多
Bacillus subtilis （B. subtilis） and Pseudomonas fluorescens （P. fluorescens） are two of the most important plant growth promoting rhizobacteria （PGPR） in agriculture. An in situ trial was conducted on greenhouse...Bacillus subtilis （B. subtilis） and Pseudomonas fluorescens （P. fluorescens） are two of the most important plant growth promoting rhizobacteria （PGPR） in agriculture. An in situ trial was conducted on greenhouse tomato （Lycopersicum esculentum Mill.） to examine the effect of two bacterial strains, Bacillus subtilis （CGMCC 1.3343） and Pseudomonas fluorescens （CGMCC 1.1802）, on tomato growth, gray mold disease control, catabolic and genetic microbial features of indigenous rhizosphere bacteria under lownitrogen conditions. A commercial inoculant （ETS） was also tested as a comparison. Both B. subtilis and P. fluorescens promoted growth and biomass of seedlings, while only B. subtilis was efficient in reducing gray mold incidence in greenhouse tomato. The two bacterial strains could colonization in tomato rhizosphere soil at the end of experiment （10 days after the last inoculation）. Different AWCD trends and DGGE patterns were got in different bacterial treatments; however, analyses of microbial diversities showed that indigenous soil microbes did not seem to have significant differences at either the catabolic or genetic level among treatments. ETS, as a commercial microbial agent, promoted plant growth and gave a higher microbial diversity in rhizosphere soil.展开更多
The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented w...The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration.展开更多
Lysine-rich protein gene （lys） was cloned from winged bean （Psophocarpus tetragonolobus （L.） DC）, and cloned into prokaryotie expression vector pHT43, the recombinant plasmid pHT43/lys were constructed and then ...Lysine-rich protein gene （lys） was cloned from winged bean （Psophocarpus tetragonolobus （L.） DC）, and cloned into prokaryotie expression vector pHT43, the recombinant plasmid pHT43/lys were constructed and then transferred into Bacillus subtilis168, upon IPTG induction, the recombinant protein was expressed, and the content of lysine was detected by HPLC. The result showed that lysine content increased by 9.85%. It was suggested that introducing lys gene into Bacillus subtilis 168 was an effective way to improve its nutrition quality.展开更多
The probiotic Bacillus subtilis （B. subtilis） was widely applied in animal production as feed additive. Lysine （Lys） and methionine （Met） were the two most important limiting amino acids in livestock animal feed...The probiotic Bacillus subtilis （B. subtilis） was widely applied in animal production as feed additive. Lysine （Lys） and methionine （Met） were the two most important limiting amino acids in livestock animal feed. Raising Lys and Met contents in B. subtilis would provide better effects for animal production and save Lys and Met supplements. We still didn＇t know whether Lys- rich and Met-rich protein genes from plants could be transfected into B. subtilis and expressed at a high level so as to improve animal production, such as milk production as an additional diet. The Lys-rich protein gene （Cflr） and Met-rich 10 ku-δ Zein were cloned from pepper anther and maize endosperm, respectively. Then they were constructed into plasmids individually and successfully cotransfected into B. subtilis. Upon IPTG induction, mRNAs and protein expressions could be observed. Lys and Met contents in the fermentation broth were raised by 65.92% and 46.39%, respectively. After feeding 200 g and 400 g· cow^-1· d^-1, transgenic B. subtilis fermentation broth, the milk yield, milk protein and milk fat contents all significantly increased. The Lys-rich protein gene （Cflr） and Met-rich 10 ku-δ Zein were successfully transfected into B. subtilis. Contents of Lys and Met in the transgenic B. subalis obviously raised and the fermentation broth of the transgenic bacteria could effectively improve milk yield and quality.展开更多
基金Project(2010A210003) supported by Henan Province Natural Sciences Research PlanProject(0910SGYS34370-2) supported by Zhengzhou City Science and Technology Research PlanProject supported by the Youth Backbone Teacher of Universities in Henan Province Grants Plan
文摘To improve antagonistic metabolites production of Bacillus subtilis strain BS501a, physical parameters of fermentation and metal inorganic salts in medium, namely initial pH value, culture temperature, fermentation time, concentrations of CaC12, FeSO4, ZnSO4, MnSO4 and MgSO4, were optimized using one-factor-at-a-time and orthogonal tests. The results show that the optimal physical parameters of fermentation are an initial pH of 7.0, a culture temperature of 30 ~C, and a fermentation time of 48 h. The optimal concentrations of metal inorganic salts in basal medium are 10.2 mmol/L CaCl2, 0.4 mmol/L FeSO4, 3.5 mmol/L ZnSO4, 0.6 mmol/L MnSO4 and 2.0 mmol/L MgSO4. Among the metal inorganic salts, MgSO4 and MnSO4 play important roles in the improvement of the antagonistic metabolites production of B. subtilis strain BS501a; especially, MgSO4 contributes a highly significant effect. The average diameter of inhibition zone of the BS501a filtered fermentation supernatant （FFS） cultured in the optimal fermentation conditions against Magnaporthe grisea DWBJ329 reaches 71.4 mm, and there is 2.4-fold increase in antifungal activity as compared with 21.2 mm under the pre-optimized conditions.
基金This work was supported by the National Natural Science Foundation of China(No.32201752)the Central Public-interest Scientific Institution Basal Research Fund(No.1610162022018),Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences.
文摘Background:In our previous study,a strain EBS03 with good biocontrol potential was screened out of 48 strains of cotton endophyte Bacillus subtilis by evaluating the controlling effect against cotton Verticillium wilt.However,its mechanism for controlling Verticillium wilt remains unclear.The objective of this study was to further clarify its con-trolling effect and mechanism against cotton Verticillium wilt.Results:The results of confrontation culture test and double buckle culture test showed that the inhibitory effects of EBS03 volatile and nonvolatile metabolite on mycelium growth of Verticillium dahliae were 70.03%and 59.00%,respectively;the inhibitory effects of sporulation and microsclerotia germination were 47.16%and 70.06%,respec-tively.In the greenhouse test,the EBS03 fermentation broth root irrigation had the highest controlling effect at 87.11%on cotton Verticillium wilt,and significantly promoted the growth of cotton seedlings.In the field experi-ment,the controlling effect of EBS03 fermentation broth to cotton Verticillium wilt was 42.54%at 60 days after cotton sowing,and the boll number per plant and boll weight in EBS03 fermentation broth seed soaking,root irrigation,and spraying treatments significantly increased by 19.48%and 7.42%,30.90%and 2.62%,15.99%and 9.20%,respec-tively.Furthermore,EBS03 improved the resistance of cotton leaves against the infection of V.dahliae,and induced the outbreak of reactive oxygen species and accumulation of callose.In addition,the results of real time fluorescent quantitative polymerase chain reaction(RT-qPCR)detection showed that EBS03 significantly induced upregulation expression level of defense-related genes PAL,POD,PPO,and PR10 in cotton leaves,enhanced cotton plant resistance to V.dahliae,and inhibited colonization level of this fungal pathogen in cotton.Conclusion:Bacillus subtilis EBS03 has a good biological defense capability,which can inhibit the growth and coloni-zation level of V.dahliae,and activate the resistance of cotton to Verticillium wilt,thus increase cotton yield.
基金Supported by the National High-tech Research and Development Program of China(2013AA102903)
文摘Bacillus subtilis （B. subtilis） and Pseudomonas fluorescens （P. fluorescens） are two of the most important plant growth promoting rhizobacteria （PGPR） in agriculture. An in situ trial was conducted on greenhouse tomato （Lycopersicum esculentum Mill.） to examine the effect of two bacterial strains, Bacillus subtilis （CGMCC 1.3343） and Pseudomonas fluorescens （CGMCC 1.1802）, on tomato growth, gray mold disease control, catabolic and genetic microbial features of indigenous rhizosphere bacteria under lownitrogen conditions. A commercial inoculant （ETS） was also tested as a comparison. Both B. subtilis and P. fluorescens promoted growth and biomass of seedlings, while only B. subtilis was efficient in reducing gray mold incidence in greenhouse tomato. The two bacterial strains could colonization in tomato rhizosphere soil at the end of experiment （10 days after the last inoculation）. Different AWCD trends and DGGE patterns were got in different bacterial treatments; however, analyses of microbial diversities showed that indigenous soil microbes did not seem to have significant differences at either the catabolic or genetic level among treatments. ETS, as a commercial microbial agent, promoted plant growth and gave a higher microbial diversity in rhizosphere soil.
基金Project(IRT0719) supported by the Program for Changjiang Scholars and Innovative Research Team in University of China Project (2004AA649370) supported by the National High-Tech Research and Development Program of China+1 种基金 Projects(50425927, 50225926) supported by the Natural Foundation for Distinguished Young Scholars Project(2007F3102) supported by Technology Foundation for Creative Young Scholars of Fujian Province, China
文摘The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration.
基金Supported by Funding of Heilongjiang Provincial Science Research Project (GB08B401-02)Innovation Team Project of Northeast Agricultural University (CXT005-1-2)
文摘Lysine-rich protein gene （lys） was cloned from winged bean （Psophocarpus tetragonolobus （L.） DC）, and cloned into prokaryotie expression vector pHT43, the recombinant plasmid pHT43/lys were constructed and then transferred into Bacillus subtilis168, upon IPTG induction, the recombinant protein was expressed, and the content of lysine was detected by HPLC. The result showed that lysine content increased by 9.85%. It was suggested that introducing lys gene into Bacillus subtilis 168 was an effective way to improve its nutrition quality.
基金Supported by High Technology Project of Ministry of Science and Technology of China(863 Project)(2013AA102504-03)Major Project of Applying Technology Research and Development of Heilongjiang Province(GA15B203)
文摘The probiotic Bacillus subtilis （B. subtilis） was widely applied in animal production as feed additive. Lysine （Lys） and methionine （Met） were the two most important limiting amino acids in livestock animal feed. Raising Lys and Met contents in B. subtilis would provide better effects for animal production and save Lys and Met supplements. We still didn＇t know whether Lys- rich and Met-rich protein genes from plants could be transfected into B. subtilis and expressed at a high level so as to improve animal production, such as milk production as an additional diet. The Lys-rich protein gene （Cflr） and Met-rich 10 ku-δ Zein were cloned from pepper anther and maize endosperm, respectively. Then they were constructed into plasmids individually and successfully cotransfected into B. subtilis. Upon IPTG induction, mRNAs and protein expressions could be observed. Lys and Met contents in the fermentation broth were raised by 65.92% and 46.39%, respectively. After feeding 200 g and 400 g· cow^-1· d^-1, transgenic B. subtilis fermentation broth, the milk yield, milk protein and milk fat contents all significantly increased. The Lys-rich protein gene （Cflr） and Met-rich 10 ku-δ Zein were successfully transfected into B. subtilis. Contents of Lys and Met in the transgenic B. subalis obviously raised and the fermentation broth of the transgenic bacteria could effectively improve milk yield and quality.
