Observation of unexpected molecular binding activity for Mu phage tail fiber chaperones.
Observation of unexpected molecular binding activity for Mu phage tail fiber chaperones.
复制标题
DOI：
10.1093/jb/mvz068
复制
发表时间：
2019-12
影响因子：
2.7
通讯作者：
K. Sakai;T. Iwazaki;E. Yamashita;A. Nakagawa;Fumiya Sakuraba;Atsushi Enomoto;M. Inagaki;S. Takeda
中科院分区：
文献类型：
--
作者：
K. Sakai;T. Iwazaki;E. Yamashita;A. Nakagawa;Fumiya Sakuraba;Atsushi Enomoto;M. Inagaki;S. Takeda
在病毒研究史上，噬菌体Mu的重要生物学特性之一就是能够扩大其宿主范围。为了扩大宿主范围，Mu噬菌体编码两个交替的尾纤维基因。经典的琥珀突变实验和Mu噬菌体基因组序列分析表明，基因S（gpS = gp 49）和基因S'（gpS' = gp 52）的基因产物（gp）是尾纤维，基因U（gpU = gp 50）和基因U '（gpU' = gp 51）的基因产物是尾纤维组装或尾纤维伴侣。根据基因取向，一对基因49 - 50或52 - 51被表达以产生不同的尾纤维，使Mu噬菌体能够识别不同的宿主细胞表面。由于包括一些噬菌体尾纤维在内的几种纤维状蛋白质利用其特异性伴侣来促进折叠和防止聚集，我们预期gp 50或gp 51将分别是gp 49和gp 52的特异性伴侣。然而，gp 49或gp 52（尾纤维亚基）分别与gp 51和gp 50一起的异源过表达结果也有效地产生可溶性Mu尾纤维。此外，我们成功地纯化了非天然gp 49-gp 51和gp 52-gp 50复合物。这些事实表明，gp 50和gp 51对gp 49和gp 52都是可互换的和功能性的。
In the history of viral research, one of the important biological features of bacteriophage Mu is the ability to expand its host range. For extending host range, the Mu phage encodes two alternate tail fiber genes. Classical amber mutation experiments and genome sequence analysis of Mu phage suggested that gene products (gp) of geneS (gpS = gp49) and gene S' (gpS' = gp52) are tail fibers and that gene products of geneU (gpU = gp50) and geneU' (gpU' = gp51) work for tail fiber assembly or tail fiber chaperones. Depending on the gene orientation, a pair of genes 49 - 50 or 52 - 51 is expressed for producing different tail fibers that enable Mu phage to recognize different host cell surface. Since several fibrous proteins including some phage tail fibers employ their specific chaperone to facilitate folding and prevent aggregation, we expected that gp50 or gp51 would be a specific chaperone for gp49 and gp52, respectively. However, heterologous overexpression results for gp49 or gp52 (tail fiber subunit) together with gp51 and gp50, respectively, were also effective in producing soluble Mu tail fibers. Moreover, we successfully purified non-native gp49-gp51 and gp52-gp50 complexes. These facts showed that gp50 and gp51 was fungible and functional for both gp49 and gp52 each other.