Molecular architecture of Streptococcus pneumoniae TIGR4 pili
Molecular architecture of Streptococcus pneumoniae TIGR4 pili
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DOI：
10.1038/emboj.2009.360
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发表时间：
2009-12-16
期刊：
影响因子：
11.4
通讯作者：
Engel, Andreas
中科院分区：
文献类型：
--
作者：
Hilleringmann, Markus;Ringler, Philippe;Engel, Andreas
虽然革兰氏阳性菌的皮利是假定的毒力因子，但对其结构知之甚少。在这里，我们描述的分子结构的菌毛1肺炎链球菌，这是一个主要的原因，发病率和死亡率在世界范围内。一个主要成分（RrgB）和两个次要成分（RrgA和RrgC）组装成菌毛。透射电镜和扫描透射电镜的结果表明，天然的皮利是约6 nm宽，可超过1 μ m长的柔性细丝。它们由一串RrgB单体形成，并具有由鼻状突起限定的极性。这些突起与单体RrgB-His的形状相关，其与RrgA-His和RrgC-His一样具有伸长的多结构域结构。RrgA和RrgC仅存在于菌毛干的相对两端，分别与它们作为细胞壁表面的粘附素和锚的假定作用相容。我们的结构分析提供了第一个直接的实验证据，表明天然S。肺炎球菌菌毛轴仅由头对尾取向的共价连接的单体RrgB亚基组成。The EMBO Journal（2009）28，3921-3930. doi：10.1038/doj.2009.360; 2009年11月26日在线发布
Although the pili of Gram-positive bacteria are putative virulence factors, little is known about their structure. Here we describe the molecular architecture of pilus-1 of Streptococcus pneumoniae, which is a major cause of morbidity and mortality worldwide. One major (RrgB) and two minor components (RrgA and RrgC) assemble into the pilus. Results from TEM and scanning transmission EM show that the native pili are approximately 6 nm wide, flexible filaments that can be over 1 mu m long. They are formed by a single string of RrgB monomers and have a polarity defined by nose-like protrusions. These protrusions correlate to the shape of monomeric RrgB-His, which like RrgA-His and RrgC-His has an elongated, multi-domain structure. RrgA and RrgC are only present at the opposite ends of the pilus shaft, compatible with their putative roles as adhesin and anchor to the cell wall surface, respectively. Our structural analyses provide the first direct experimental evidence that the native S. pneumoniae pilus shaft is composed exclusively of covalently linked monomeric RrgB subunits oriented head-to-tail. The EMBO Journal (2009) 28, 3921-3930. doi: 10.1038/emboj.2009.360; Published online 26 November 2009