• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Infection and immunity >Characterization of the Fibrinogen Binding Domain of Bacteriophage Lysin from Streptococcus mitis
【24h】

Characterization of the Fibrinogen Binding Domain of Bacteriophage Lysin from Streptococcus mitis

机译：噬菌体溶血素来自纤维链球菌的纤维蛋白原结合域的表征

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The binding of bacteria to human platelets is a likely central mechanism in the pathogenesis of infective endocarditis. Platelet binding by Streptococcus mitis SF100 is mediated in part by a lysin encoded by the lysogenic bacteriophage SM1. In addition to its role in the phage life cycle, lysin mediates the binding of S. mitis to human platelets via its interaction with fibrinogen on the platelet surface. To better define the region of lysin mediating fibrinogen binding, we tested a series of purified lysin truncation variants for their abilities to bind this protein. These studies revealed that the fibrinogen binding domain of lysin is contained within the region spanned by amino acid residues 102 to 198 (lysin102–198). This region has no sequence homology to other known fibrinogen binding proteins. Lysin102–198 bound fibrinogen comparably to full-length lysin and with the same selectivity for the fibrinogen Aα and Bβ chains. Lysin102–198 also inhibited the binding in vitro of S. mitis to human fibrinogen and platelets. When assessed by platelet aggregometry, the disruption of the lysin gene in SF100 resulted in a significantly longer time to the onset of aggregation of human platelets than that of the parent strain. The preincubation of platelets with purified lysin102–198 also delayed the onset of aggregation by SF100. These results indicate that the binding of lysin to fibrinogen is mediated by a specific domain of the phage protein and that this interaction is important for both platelet binding and aggregation by S. mitis.
机译：细菌与人血小板的结合是感染性心内膜炎的发病机制中可能的主要机制。溶血性噬菌体SM1编码的溶素部分介导了链球菌SF100对血小板的结合。溶血素除了在噬菌体生命周期中发挥作用外，还通过其与血小板表面血纤蛋白原的相互作用介导了链球菌与人血小板的结合。为了更好地定义溶血素介导纤维蛋白原结合的区域，我们测试了一系列纯化的溶素截短变体与蛋白质结合的能力。这些研究表明，溶血素的纤维蛋白原结合结构域包含在氨基酸残基102至198（溶血素 102-198 ）所跨越的区域内。该区域与其他已知的纤维蛋白原结合蛋白没有序列同源性。溶素 102–198 与血纤蛋白溶酶相当地结合于全长溶素，并且对血纤蛋白原Aα和Bβ链的选择性相同。溶素 102–198 还抑制了链球菌体外与人纤维蛋白原和血小板的结合。当通过血小板凝集测定法评估时，SF100中溶血素基因的破坏导致人血小板凝集开始的时间比亲本菌株明显更长。血小板与纯化的溶素 102–198 的预温育也延迟了SF100聚集的开始。这些结果表明，溶菌素与纤维蛋白原的结合是由噬菌体蛋白的特定结构域介导的，这种相互作用对于血小板结合和链球菌的聚集都是重要的。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号