Drought is a bottleneck for worldwide soybean production which is getting more serious as the climate continues to worsen. Dehydration responsive element binding（DREB） is a kind of transcription factor that regulate...Drought is a bottleneck for worldwide soybean production which is getting more serious as the climate continues to worsen. Dehydration responsive element binding（DREB） is a kind of transcription factor that regulates the expression of stress tolerance-related genes in response to drought, high salinity and cold stress in plant. Soybean with DREB gene possesses the drought resisting capability which is helpful to increase the yield. However, the potential risk of genetically modified plants（GMPs） on soil microbial community is still in debate. In order to understand the effects of transgenic DREB soybean on the nitrogen-fixing bacteria, the diversity of nif H gene in pot experiments planted transgenic soybean and near-isogenic nontransgenic soybean under normal water condition and drought stress condition was analyzed by PCR-DGGE and sequence analysis. The results showed that transgenic soybean under normal water condition decrease the diversity of the nitrogen-fixing bacteria in the seeding stage and flowering stage, but had no notable effect in other stages. Under drought stress, transgenic soybean reduced the diversity of the nitrogen-fixing bacteria in the flowering stage, but had no notable effects on other stages. Phylogenic analysis revealed that g7, g13, g15 and g19 had a close relationship with Alphaproteobacteria, g12 had a close relationship with Azonexus, others were related to Betaproteobacteria and Burkholderia.展开更多
Objective: The aim of the present study was to assess the antithrombotic properties of different strains of orally available antithrombotic lactic acid bacteria (LAB). Research Methods & Procedures: Antithrombotic...Objective: The aim of the present study was to assess the antithrombotic properties of different strains of orally available antithrombotic lactic acid bacteria (LAB). Research Methods & Procedures: Antithrombotic activity, antiplatelet reactivity and/or thrombolytic activity, were measured in seven strains of LAB and LAB cell-free-extracts (LAB filtrates) using the shear-induced platelet reactivity/thrombolytic activity, The Global Thrombosis Test (GTT), with non-anticoagulated rat blood in vitro. Subsequently, the most potent antithrombotic strains identified in vitro were assessed in vivo after oral administration in mouse carotid arteries using a helium-neon laser-induced thrombosis model. Result: Five strains out of seven LAB (Lactobacillus paracasei KW 3100, Lactobacillus fermentum NBRC 3961, Lactobacillus pentosus JCM 8333, Leuconostoc oeni Elios 1, Pediococcus pentosaceus NK-2) promoted significant endogenous thrombolysis in vitro. In addition, one strain (Lactobacillus fermentum NBRC 3961) significantly inhibited shear-induced platelet re-activity. Three antithrombotic strains, Lactobacillus fermentum NBRC 3961, Leuconostoc oeni Elios 1, and Lactobacillus pentosus JCM 8333, were further assessed in vivo. The results demonstrated that filtrates, and the cells per se of these LAB, modulated antiplatelet activity and/or thrombolytic activity, and that the antithrombotic mechanisms were mainly influenced by protein content (60% - 70% of dry matter). Conclusion: The findings suggested that some strains of lactic acid bacteria could usefully provide the basis for the production of oral antithrombotic probiotics.展开更多
为明确不同土壤条件对甘蔗内生固氮菌多样性的影响,对分别种植在红壤土和水稻土的4个甘蔗品种的内生固氮菌进行分离和鉴定,并利用数学生态学方法分析不同来源内生固氮菌的多样性。结果表明,从红壤土的甘蔗组织中分离筛选获得23个内生固...为明确不同土壤条件对甘蔗内生固氮菌多样性的影响,对分别种植在红壤土和水稻土的4个甘蔗品种的内生固氮菌进行分离和鉴定,并利用数学生态学方法分析不同来源内生固氮菌的多样性。结果表明,从红壤土的甘蔗组织中分离筛选获得23个内生固氮菌株,它们在基于16S r DNA序列分析结果上属于9个不同的菌属;而从水稻土的甘蔗组织中获得59个内生固氮菌株,分类上属于19个不同的菌属。群落生态学分析结果显示,来源于水稻土的甘蔗内生固氮菌的群落丰富度指数(dma)、多样性指数(H')以及均匀度指数(Jsw)均明显高于红壤土,表明水稻土条件下的甘蔗内生固氮菌群落结构相对复杂、稳定和均匀;而相同土壤条件下4个甘蔗品种间的内生固氮菌丰富度指数和多样性指数差异并不明显。本研究结果反映了土壤生态条件是影响甘蔗内生固氮菌多样性的重要因子。展开更多
基金Supported by the Special Scientific Fund for Non-profit Environmental Industry(2010467038)
文摘Drought is a bottleneck for worldwide soybean production which is getting more serious as the climate continues to worsen. Dehydration responsive element binding（DREB） is a kind of transcription factor that regulates the expression of stress tolerance-related genes in response to drought, high salinity and cold stress in plant. Soybean with DREB gene possesses the drought resisting capability which is helpful to increase the yield. However, the potential risk of genetically modified plants（GMPs） on soil microbial community is still in debate. In order to understand the effects of transgenic DREB soybean on the nitrogen-fixing bacteria, the diversity of nif H gene in pot experiments planted transgenic soybean and near-isogenic nontransgenic soybean under normal water condition and drought stress condition was analyzed by PCR-DGGE and sequence analysis. The results showed that transgenic soybean under normal water condition decrease the diversity of the nitrogen-fixing bacteria in the seeding stage and flowering stage, but had no notable effect in other stages. Under drought stress, transgenic soybean reduced the diversity of the nitrogen-fixing bacteria in the flowering stage, but had no notable effects on other stages. Phylogenic analysis revealed that g7, g13, g15 and g19 had a close relationship with Alphaproteobacteria, g12 had a close relationship with Azonexus, others were related to Betaproteobacteria and Burkholderia.
文摘Objective: The aim of the present study was to assess the antithrombotic properties of different strains of orally available antithrombotic lactic acid bacteria (LAB). Research Methods & Procedures: Antithrombotic activity, antiplatelet reactivity and/or thrombolytic activity, were measured in seven strains of LAB and LAB cell-free-extracts (LAB filtrates) using the shear-induced platelet reactivity/thrombolytic activity, The Global Thrombosis Test (GTT), with non-anticoagulated rat blood in vitro. Subsequently, the most potent antithrombotic strains identified in vitro were assessed in vivo after oral administration in mouse carotid arteries using a helium-neon laser-induced thrombosis model. Result: Five strains out of seven LAB (Lactobacillus paracasei KW 3100, Lactobacillus fermentum NBRC 3961, Lactobacillus pentosus JCM 8333, Leuconostoc oeni Elios 1, Pediococcus pentosaceus NK-2) promoted significant endogenous thrombolysis in vitro. In addition, one strain (Lactobacillus fermentum NBRC 3961) significantly inhibited shear-induced platelet re-activity. Three antithrombotic strains, Lactobacillus fermentum NBRC 3961, Leuconostoc oeni Elios 1, and Lactobacillus pentosus JCM 8333, were further assessed in vivo. The results demonstrated that filtrates, and the cells per se of these LAB, modulated antiplatelet activity and/or thrombolytic activity, and that the antithrombotic mechanisms were mainly influenced by protein content (60% - 70% of dry matter). Conclusion: The findings suggested that some strains of lactic acid bacteria could usefully provide the basis for the production of oral antithrombotic probiotics.
文摘为明确不同土壤条件对甘蔗内生固氮菌多样性的影响,对分别种植在红壤土和水稻土的4个甘蔗品种的内生固氮菌进行分离和鉴定,并利用数学生态学方法分析不同来源内生固氮菌的多样性。结果表明,从红壤土的甘蔗组织中分离筛选获得23个内生固氮菌株,它们在基于16S r DNA序列分析结果上属于9个不同的菌属;而从水稻土的甘蔗组织中获得59个内生固氮菌株,分类上属于19个不同的菌属。群落生态学分析结果显示,来源于水稻土的甘蔗内生固氮菌的群落丰富度指数(dma)、多样性指数(H')以及均匀度指数(Jsw)均明显高于红壤土,表明水稻土条件下的甘蔗内生固氮菌群落结构相对复杂、稳定和均匀;而相同土壤条件下4个甘蔗品种间的内生固氮菌丰富度指数和多样性指数差异并不明显。本研究结果反映了土壤生态条件是影响甘蔗内生固氮菌多样性的重要因子。
