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海洋芽孢杆菌(Bacillus marinus)B-9987菌株抑制病原真菌机理的研究 总被引:3,自引:0,他引:3
摘要:【目的】:探讨海洋芽孢杆菌(Bacillus marinus)B-9987菌株的代谢产物BMME-1,对植物病原真菌茄链格孢菌的抑菌作用机理。【方法】分别使用分光光法、气相色谱-质谱GC-MS联用技术、红外光谱法等,检测了BMME-1处理病原真菌后,菌体渗透性、细胞壁及细胞膜成份的变化。【结果】BMME-1对茄链格孢菌的抑菌中浓度(MIC50)为6.2 mg/L,最小杀菌浓度(MFC)为50 mg/L,在MIC50浓度或高于此浓度处理靶标菌,将导致菌体蛋白质、核酸等大分子物质的外流;处理菌株葡聚糖结 相似文献
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藻胆蛋白(phycobiliprotein)是蓝藻和红藻藻胆体的组成部分,是光合作用集光复合体的组成部分,一般由α和β亚基构成,每个亚基含1~4个辅基色素,从而使藻胆蛋白具有特定的光谱吸收性质。根据这些吸收光谱性质,可以将藻胆蛋白分为:别藻蓝蛋白(APC)、藻蓝蛋白(PC)和藻红蛋白(PE)等,在某些缺乏PE而有异形胞的蓝藻中存在充当PE天线捕光功能的藻红蓝蛋白(PEC)〔1〕。藻胆蛋白可用于天然食用色素、化妆品色素和制药行业,还可作为免疫检测、荧光显微技术和流式细胞荧光测定法技术方面的荧光探针。特别是本工作研究的层理鞭枝藻(简称M.laminosu… 相似文献
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James Love Filippo Mancia Lawrence Shapiro Marco Punta Burkhard Rost Mark Girvin Da-Neng Wang Ming Zhou John F. Hunt Thomas Szyperski Eric Gouaux Roderick MacKinnon Ann McDermott Barry Honig Masayori Inouye Gaetano Montelione Wayne A. Hendrickson 《Journal of structural and functional genomics》2010,11(3):191-199
The New York Consortium on Membrane Protein Structure (NYCOMPS) was formed to accelerate the acquisition of structural information on membrane proteins by applying a structural genomics approach. NYCOMPS comprises a bioinformatics group, a centralized facility operating a high-throughput cloning and screening pipeline, a set of associated wet labs that perform high-level protein production and structure determination by x-ray crystallography and NMR, and a set of investigators focused on methods development. In the first three years of operation, the NYCOMPS pipeline has so far produced and screened 7,250 expression constructs for 8,045 target proteins. Approximately 600 of these verified targets were scaled up to levels required for structural studies, so far yielding 24 membrane protein crystals. Here we describe the overall structure of NYCOMPS and provide details on the high-throughput pipeline. 相似文献
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Lei Mao Juncai Chen Quanhui Peng Aiming Zhou Zhisheng Wang 《Biological trace element research》2013,155(1):132-141
Zinc has been shown to be an inhibitor of apoptosis for many years. The present study was designed to investigate effects of three zinc chemical forms on H2O2-induced cell apoptosis in IEC-6 cells via analysis of cell vitality, LDH activity, apoptosis percentage, caspase-3 activity, and Bcl-2, Bax, and caspase-3, -8, and -9 gene expression. Cells were divided into H2O2 and zinc sources+H2O2 groups, and there are three different zinc sources [zinc oxide nanoparticle (nano-ZnO), zinc oxide (ZnO), and zinc sulfate (ZnSO4)] and three concentrations (normal = 25 μM, medium = 50 μM, and high = 100 μM) used in this article. In the present study, we found the striking cytotoxicity of H2O2 higher than 200 μM on cell vitality, LDH activity, and apoptosis percentage in the cells using five different concentrations (50, 100, 200, 400, and 800 μM) of H2O2 for 4 h. Moreover, we observed that cell vitality was increased, LDH activity and apoptotic percentage were decreased, and gene expression level of Bax and caspase-3 and -9 was markedly reduced, while gene expression level of Bcl-2 and ratio of Bcl-2/Bax were increased in normal concentration groups of nano-ZnO and ZnSO4 compared with H2O2 group, but no significant difference was observed in caspase-8 gene expression. Furthermore, medium or, more intensely, high concentrations of nano-ZnO and ZnSO4 enhanced H2O2-induced cell apoptosis. Compared with nano-ZnO and ZnSO4, ZnO showed weakest protective effect on H2O2-induced apoptosis at normal concentration and was less toxic to cells at high level. Taken together, we proposed that preventive and protective effects of zinc on H2O2-induced cell apoptosis varied in IEC-6 cells with its chemical forms and concentrations, and maybe for the first time, we suggested that nano-ZnO have a protective effect on H2O2-induced cell apoptosis in IEC-6 cells. 相似文献
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