本文主要研究内容
作者王贵珍（2019）在《白皮杉醇抑制胆固醇依赖型细胞溶素活性及作用机制》一文中研究指出：胆固醇依赖型细胞溶素(Cholesterol-dependent cytolysins,CDCs)是多种革兰氏阳性病原菌在感染过程中分泌的一大类毒素,其典型特征是能在靶细胞上打孔,裂解多种细胞,因此也被称为成孔毒素或溶血素。分泌CDCs的革兰氏阳性病原菌能引发人畜多种感染性疾病,如脑膜炎、菌血症、关节炎、肺炎、胃肠炎和坏死性肠炎等,严重威胁人类健康、畜牧业经济效益和食品安全。40多种革兰氏阳性病原菌能在感染过程中分泌CDCs,其中单增李斯特菌细胞溶素(Listeriolysin O,LLO)、猪链球菌细胞溶素(Suilysin,SLY)和肺炎链球菌细胞溶素(Pneumolysin,PLY)分别由单核增生李斯特菌(L.monocytogenes)、猪链球菌(S.suis)和肺炎链球菌(S.pneumonia)分泌,是CDCs家族中典型代表性成员。研究表明细胞溶素在其病原菌感染过程中发挥多方面关键作用,如裂解多种细胞,导致细胞内容物泄露;促进病原菌穿过血脑屏障,引发脑膜炎;帮助细菌逃避免疫系统清除作用;诱导细胞凋亡;降低机体免疫力,引发炎症等,这些重要作用使其成为筛选抗分泌CDCs革兰氏阳性病原菌抗菌剂的重要靶点。此外,研究表明CDCs家族成员一级结构有高度同源性、空间结构存在高度相似性、有相似的成孔机制和相近的生物学功能,这些共同特征也为以CDCs为靶标筛选广谱抗毒力抑制剂奠定了基础。本研究以CDCs家族中典型成员LLO、SLY和PLY为靶标,获得食源性天然化合物白皮杉醇抑制剂,抗菌试验表明白皮杉醇在有效抑制成孔活性浓度条件下不影响病原菌的生长;蛋白免疫印迹试验发现白皮杉醇能直接抑制CDCs寡聚体的形成。细胞水平上,白皮杉醇显著降低了分泌CDCs病原菌介导的细胞毒性及炎症反应。动物试验发现白皮杉醇对单增李斯特菌感染小鼠表现出了系统性的保护作用,体现在降低感染小鼠死亡率,降低单增李斯特菌靶器官(脾脏和肝脏)细菌定植数和炎症因子水平,缓解了炎症反应。基于计算生物学和生物化学方法探究并验证了白皮杉醇与CDCs作用机制。利用分子对接和分子动力学模拟方法获得了白皮杉醇与CDCs稳定复合物体系,分析了研究对象之间的具体结合模式、结合过程中氨基酸自由能贡献、蛋白质中各氨基酸残基在结合白皮杉醇前后柔性的变化及氢键作用,发现白皮杉醇结合在CDCs家族成员第2结构域与第4结构域的交界处,结合后引发CDCs空间构象发生变化,导致第2结构域与第4结构域之间的夹角变大,第4结构域不能充分与靶细胞膜上的胆固醇受体结合,阻碍了寡聚体的形成,引发了成孔活性的降低。天冬酰胺在白皮杉醇与CDCs成员蛋白的结合过程中贡献了能量,精氨酸和酪氨酸仅在白皮杉醇与PLY和SLY的结合过程发挥了作用。白皮杉醇与PLY和SLY的结合过程中存在氢键作用,整个结合过程中氢键的稳定性高于60%,表明氢键是SLY和PLY与白皮杉醇结合过程中重要分子间作用力,对复合物体系的稳定提供重要作用。另外通过Lig Plus软件和径向分布函数分析发现白皮杉醇的间位羟基是氢键形成的关键基团,最后通过氨基酸定点突变、荧光淬灭和突变后结合自由能计算确证了分子动力学模拟结果的可靠性和可信性。分子机制的探索和阐明为开发抗CDCs病原菌广谱抗菌剂提供了重要理论基础。
Abstract
dan gu chun yi lai xing xi bao rong su (Cholesterol-dependent cytolysins,CDCs)shi duo chong ge lan shi yang xing bing yuan jun zai gan ran guo cheng zhong fen bi de yi da lei du su ,ji dian xing te zheng shi neng zai ba xi bao shang da kong ,lie jie duo chong xi bao ,yin ci ye bei chen wei cheng kong du su huo rong xie su 。fen bi CDCsde ge lan shi yang xing bing yuan jun neng yin fa ren chu duo chong gan ran xing ji bing ,ru nao mo yan 、jun xie zheng 、guan jie yan 、fei yan 、wei chang yan he huai si xing chang yan deng ,yan chong wei xie ren lei jian kang 、chu mu ye jing ji xiao yi he shi pin an quan 。40duo chong ge lan shi yang xing bing yuan jun neng zai gan ran guo cheng zhong fen bi CDCs,ji zhong chan zeng li si te jun xi bao rong su (Listeriolysin O,LLO)、zhu lian qiu jun xi bao rong su (Suilysin,SLY)he fei yan lian qiu jun xi bao rong su (Pneumolysin,PLY)fen bie you chan he zeng sheng li si te jun (L.monocytogenes)、zhu lian qiu jun (S.suis)he fei yan lian qiu jun (S.pneumonia)fen bi ,shi CDCsjia zu zhong dian xing dai biao xing cheng yuan 。yan jiu biao ming xi bao rong su zai ji bing yuan jun gan ran guo cheng zhong fa hui duo fang mian guan jian zuo yong ,ru lie jie duo chong xi bao ,dao zhi xi bao nei rong wu xie lou ;cu jin bing yuan jun chuan guo xie nao bing zhang ,yin fa nao mo yan ;bang zhu xi jun tao bi mian yi ji tong qing chu zuo yong ;you dao xi bao diao wang ;jiang di ji ti mian yi li ,yin fa yan zheng deng ,zhe xie chong yao zuo yong shi ji cheng wei shai shua kang fen bi CDCsge lan shi yang xing bing yuan jun kang jun ji de chong yao ba dian 。ci wai ,yan jiu biao ming CDCsjia zu cheng yuan yi ji jie gou you gao du tong yuan xing 、kong jian jie gou cun zai gao du xiang shi xing 、you xiang shi de cheng kong ji zhi he xiang jin de sheng wu xue gong neng ,zhe xie gong tong te zheng ye wei yi CDCswei ba biao shai shua an pu kang du li yi zhi ji dian ding le ji chu 。ben yan jiu yi CDCsjia zu zhong dian xing cheng yuan LLO、SLYhe PLYwei ba biao ,huo de shi yuan xing tian ran hua ge wu bai pi sha chun yi zhi ji ,kang jun shi yan biao ming bai pi sha chun zai you xiao yi zhi cheng kong huo xing nong du tiao jian xia bu ying xiang bing yuan jun de sheng chang ;dan bai mian yi yin ji shi yan fa xian bai pi sha chun neng zhi jie yi zhi CDCsgua ju ti de xing cheng 。xi bao shui ping shang ,bai pi sha chun xian zhe jiang di le fen bi CDCsbing yuan jun jie dao de xi bao du xing ji yan zheng fan ying 。dong wu shi yan fa xian bai pi sha chun dui chan zeng li si te jun gan ran xiao shu biao xian chu le ji tong xing de bao hu zuo yong ,ti xian zai jiang di gan ran xiao shu si wang lv ,jiang di chan zeng li si te jun ba qi guan (pi zang he gan zang )xi jun ding zhi shu he yan zheng yin zi shui ping ,huan jie le yan zheng fan ying 。ji yu ji suan sheng wu xue he sheng wu hua xue fang fa tan jiu bing yan zheng le bai pi sha chun yu CDCszuo yong ji zhi 。li yong fen zi dui jie he fen zi dong li xue mo ni fang fa huo de le bai pi sha chun yu CDCswen ding fu ge wu ti ji ,fen xi le yan jiu dui xiang zhi jian de ju ti jie ge mo shi 、jie ge guo cheng zhong an ji suan zi you neng gong suo 、dan bai zhi zhong ge an ji suan can ji zai jie ge bai pi sha chun qian hou rou xing de bian hua ji qing jian zuo yong ,fa xian bai pi sha chun jie ge zai CDCsjia zu cheng yuan di 2jie gou yu yu di 4jie gou yu de jiao jie chu ,jie ge hou yin fa CDCskong jian gou xiang fa sheng bian hua ,dao zhi di 2jie gou yu yu di 4jie gou yu zhi jian de ga jiao bian da ,di 4jie gou yu bu neng chong fen yu ba xi bao mo shang de dan gu chun shou ti jie ge ,zu ai le gua ju ti de xing cheng ,yin fa le cheng kong huo xing de jiang di 。tian dong xian an zai bai pi sha chun yu CDCscheng yuan dan bai de jie ge guo cheng zhong gong suo le neng liang ,jing an suan he lao an suan jin zai bai pi sha chun yu PLYhe SLYde jie ge guo cheng fa hui le zuo yong 。bai pi sha chun yu PLYhe SLYde jie ge guo cheng zhong cun zai qing jian zuo yong ,zheng ge jie ge guo cheng zhong qing jian de wen ding xing gao yu 60%,biao ming qing jian shi SLYhe PLYyu bai pi sha chun jie ge guo cheng zhong chong yao fen zi jian zuo yong li ,dui fu ge wu ti ji de wen ding di gong chong yao zuo yong 。ling wai tong guo Lig Plusruan jian he jing xiang fen bu han shu fen xi fa xian bai pi sha chun de jian wei qiang ji shi qing jian xing cheng de guan jian ji tuan ,zui hou tong guo an ji suan ding dian tu bian 、ying guang cui mie he tu bian hou jie ge zi you neng ji suan que zheng le fen zi dong li xue mo ni jie guo de ke kao xing he ke xin xing 。fen zi ji zhi de tan suo he chan ming wei kai fa kang CDCsbing yuan jun an pu kang jun ji di gong le chong yao li lun ji chu 。
论文参考文献
论文详细介绍
论文作者分别是来自吉林大学的王贵珍，发表于刊物吉林大学2019-06-25论文，是一篇关于胆固醇依赖型细胞溶素论文,白皮杉醇论文,分子对接论文,分子模拟论文,抗毒力论文,抗感染论文,吉林大学2019-06-25论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自吉林大学2019-06-25论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：胆固醇依赖型细胞溶素论文; 白皮杉醇论文; 分子对接论文; 分子模拟论文; 抗毒力论文; 抗感染论文; 吉林大学2019-06-25论文;