[Objective] The study aimed to explore the antibacterial activity and stability of antagonistic bacteria P72 against wheat scab.[Method] The Bacillus subtilis P72 was inoculated into fermentation media with the inocul...[Objective] The study aimed to explore the antibacterial activity and stability of antagonistic bacteria P72 against wheat scab.[Method] The Bacillus subtilis P72 was inoculated into fermentation media with the inoculation amount 5%,then cultured on shaking table at 28 ℃ for 48 h and centrifuged at 8 000 r/min for 10 min.The supernatant of fermentation broth was purified and then the genetic stability,thermal stability and pH stability were detected.[Result] By DEAE-52 ion exchange chromatography,the protein eluted by 0.5 mol/L NaCl solution possessed the strongest antagonistic ability against wheat scab pathogen.The SDS-PAGE electrophoresis showed that the molecular weight of the purified protein with antibacterial effect was 40 kD.By stability test,the antibacterial substance produced by P72 strain showed heritable antagonistic activity,high stability below 60 ℃,stability to acid and unstability to alkali.[Conclusion] The antagonistic bacteria P72 had strong antagonistic ability to wheat scab pathogen,stable antibacterial activity and thermal stability,so it would possess a wide development prospect.展开更多
Primary biliary cirrhosis （PBC） is a progressive cho- lestatic liver disease characterized by the immune- mediated destruction of biliary epithelial cells in small intrahepatic bile ducts. The disease is characteriz...Primary biliary cirrhosis （PBC） is a progressive cho- lestatic liver disease characterized by the immune- mediated destruction of biliary epithelial cells in small intrahepatic bile ducts. The disease is characterized by circulating antimitochondrial antibodies （AMAs） as well as disease-specific antinuclear antibodies, cholestatic liver function tests, and characteristic histological fea- tures, including granulomas. A variety of organisms are involved in granuloma formation, of which mycobacte- ria are the most commonly associated. This has led to the hypothesis that mnycobacteria may be involved in the pathogenesis of PBC, along with other infectious agents. Additionally, AMAs are found in a subgroup of patients with rnycobacterial infections, such as lep- rosy and pulmonary tuberculosis. Antibodies against species-specific mycobacterial proteins have been re- ported in patients with PBC, but it is not clear whether these antibodies are specific for the disease. In addi- tion, data in support of the involvement of the role of molecular mimicry between rnycobacterial and human mitochondrial antigens as triggers of cross-reactive im- mune responses leading to the loss of immunological tolerance, and the induction of pathological features have been published. Thus, antibodies against myco- bacterial heat shock protein appear to cross-recognize AMA-specific autoantigens, but it is not clear whether these autoantibodies are mycobacterium-species-spe- cific, and whether they are pathogenic or incidental. The view that mycobacteria are infectious triggers of PBC is intriguing, but the data provided so far are not conclusive.展开更多
文摘[Objective] The study aimed to explore the antibacterial activity and stability of antagonistic bacteria P72 against wheat scab.[Method] The Bacillus subtilis P72 was inoculated into fermentation media with the inoculation amount 5%,then cultured on shaking table at 28 ℃ for 48 h and centrifuged at 8 000 r/min for 10 min.The supernatant of fermentation broth was purified and then the genetic stability,thermal stability and pH stability were detected.[Result] By DEAE-52 ion exchange chromatography,the protein eluted by 0.5 mol/L NaCl solution possessed the strongest antagonistic ability against wheat scab pathogen.The SDS-PAGE electrophoresis showed that the molecular weight of the purified protein with antibacterial effect was 40 kD.By stability test,the antibacterial substance produced by P72 strain showed heritable antagonistic activity,high stability below 60 ℃,stability to acid and unstability to alkali.[Conclusion] The antagonistic bacteria P72 had strong antagonistic ability to wheat scab pathogen,stable antibacterial activity and thermal stability,so it would possess a wide development prospect.
文摘Primary biliary cirrhosis （PBC） is a progressive cho- lestatic liver disease characterized by the immune- mediated destruction of biliary epithelial cells in small intrahepatic bile ducts. The disease is characterized by circulating antimitochondrial antibodies （AMAs） as well as disease-specific antinuclear antibodies, cholestatic liver function tests, and characteristic histological fea- tures, including granulomas. A variety of organisms are involved in granuloma formation, of which mycobacte- ria are the most commonly associated. This has led to the hypothesis that mnycobacteria may be involved in the pathogenesis of PBC, along with other infectious agents. Additionally, AMAs are found in a subgroup of patients with rnycobacterial infections, such as lep- rosy and pulmonary tuberculosis. Antibodies against species-specific mycobacterial proteins have been re- ported in patients with PBC, but it is not clear whether these antibodies are specific for the disease. In addi- tion, data in support of the involvement of the role of molecular mimicry between rnycobacterial and human mitochondrial antigens as triggers of cross-reactive im- mune responses leading to the loss of immunological tolerance, and the induction of pathological features have been published. Thus, antibodies against myco- bacterial heat shock protein appear to cross-recognize AMA-specific autoantigens, but it is not clear whether these autoantibodies are mycobacterium-species-spe- cific, and whether they are pathogenic or incidental. The view that mycobacteria are infectious triggers of PBC is intriguing, but the data provided so far are not conclusive.
