Changes in bacteriophage T7 virion structure at the initiation of infection
Changes in bacteriophage T7 virion structure at the initiation of infection
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DOI：
10.1016/j.virol.2005.06.039
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发表时间：
2005-09-30
期刊：
影响因子：
3.7
通讯作者：
Molineux, IJ
中科院分区：
文献类型：
--
作者：
Kemp, P;Garcia, LR;Molineux, IJ
在感染开始时，从噬菌体T7病毒粒子中喷射出五种蛋白质。内部核心的三种已知蛋白质进入感染细胞；这三者都必须从成熟病毒粒子的结构中分解，并且几乎完全展开，才能离开头部并通过首尾连接处。两个小的蛋白质，基因6.7和7.3的产物，也从感染病毒粒子中喷射出来。Gp6.7和gp7.3以前没有被描述为结构病毒粒子成分，导致对病毒粒子蛋白质化学计量学的重新评估。Gp6.7存在于无尾颗粒中，被定义为头部蛋白，而gp7.3则定位于尾部。基因6.7可能在形态发生中起重要作用；这种晚期基因有缺陷的突变体产生的后代数量减少。基因7.3对于病毒粒子的组装是必不可少的，但是，尽管通常存在，其产物gp7.3在成熟粒子中并不需要。在gp7.3缺失的情况下组装的颗粒含有尾纤维，但不能吸附到细胞上。(c) 2005爱思唯尔公司版权所有。
Five proteins are ejected from the bacteriophage T7 virion at the initiation of infection. The three known proteins of the internal core enter the infected cell; all three must both disaggregate from their structure in the mature virion and also almost completely unfold in order to leave the head and pass through the head-tail connector. Two small proteins, the products of genes 6.7 and 7.3, also are ejected from the infecting virion. Gp6.7 and gp7.3 were not previously described as structural virion components, leading to a re-appraisal of the stoichiometry of virion proteins. Gp6.7 is found in tail-less particles and is defined as a head protein, whereas gp7.3 is localized in the tail. Gene 6.7 may be important in morphogenesis; mutants defective in this late gene yield a reduced burst of progeny. Gene 7.3 is essential for virion assembly but, although normally present, its product gp7.3 is not required in a mature particle. Particles assembled in the absence of gp7.3 contain tail fibers but fail to adsorb to cells. (c) 2005 Elsevier Inc. All rights reserved.