The neck of bacteriophage T4 is a ring-like formed by a hetero-oligomer of gp13 and structure gp14
The neck of bacteriophage T4 is a ring-like formed by a hetero-oligomer of gp13 and structure gp14
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DOI：
10.1016/j.bbapap.2007.05.011
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发表时间：
2007-08-01
影响因子：
3.2
通讯作者：
Arisaka, Fumio
中科院分区：
文献类型：
--
作者：
Akhter, Tahmina;Zhao, Li;Arisaka, Fumio
将DNA包装到噬菌体T4的头部完成后，在头部的入口顶点形成颈部，为尾部附着做好准备。颈部的主要成分是gp13和gpl4（gp：基因产物），分别由309和256个氨基酸残基组成。为了阐明颈部的结构和亚基排列，构建了基因13和基因14的过表达系统并纯化至同质。 gp13和gpl4的远紫外圆二色性(CD)光谱表明gp13富含α螺旋，而gp14富含β折叠。 gp13 和 gpl4 的沉降速度分析表明，这两种蛋白质在溶液中均以单体形式存在。两种蛋白质的摩擦比（fifo）表明gp 14比gp 13具有更细长的形状。尽管分离的gp 13和gp 14在生理条件下混合时不会相互作用，但在用硫酸铵处理后，它们形成化学计量比为10:5的异源低聚物复合物。该复合物的电子显微镜显示其形成直径为15 nm的环状结构。 (c) 2007 Elsevier B.V. 保留所有权利。
After packaging of DNA into the head of bacteriophage T4 is completed, a neck is formed at the portal vertex of the head to be ready for the tail attachment. The main components of the neck are gp13 and gpl4 (gp: gene product), which consist of 309 and 256 amino acid residues, respectively. In order to elucidate the structure and subunit arrangement in the neck, overexpression systems of gene 13 and gene 14 were constructed and purified to homogeneity. Far-UV circular dichroism (CD) spectra of gp13 and gpl4 indicated that gp13 is rich in alpha-helices whereas gp14 is rich in beta-sheets. Sedimentation velocity analysis of gp13 and gpl4 revealed that both proteins are present as monomers in solution. The frictional ratios (fifo) of the two proteins indicated that gp 14 has a more elongated shape than gp 13. Although isolated gp 13 and gp 14 do not interact with each other when mixed under physiological conditions, they form a hetero-oligomer complex with the stoichiometry of 10:5 after treatment with ammonium sulfate. Electron microscopy of this complex has shown that it forms a ring-like structure of 15 nm in diameter. (c) 2007 Elsevier B.V. All rights reserved.