Chlamydiaphage Chp2, a skeleton in the φX174 closet:: Scaffolding protein and procapsid identification
Chlamydiaphage Chp2, a skeleton in the φX174 closet:: Scaffolding protein and procapsid identification
复制标题
DOI：
10.1128/jb.186.22.7571-7574.2004
复制
发表时间：
2004-11-01
影响因子：
3.2
通讯作者：
Fane, BA
中科院分区：
文献类型：
--
作者：
Clarke, IN;Cutcliffe, LT;Fane, BA
衣原体噬菌体Chp 2是微病毒科的成员，其中噬菌体phiX 174是模式种。虽然被分组在同一个家族中，但大肠杆菌微病毒科和Chp 2样病毒（它们感染专性细胞内寄生细菌）之间的关系相当遥远，在结构蛋白含量和支架蛋白依赖性方面存在重大差异。为了研究Chp 2的形态发生，通过平衡沉降和速率区带沉降从感染的Chlamophila abortus中分离出大颗粒。在这些检测测定中使用仅识别组装的病毒外壳蛋白的单克隆抗体。因此，检测到的颗粒代表病毒体和/或衣壳后形成组装中间体。检测到两种不同的颗粒类型，蛋白质和DNA含量不同。填充颗粒缺乏VP 3，推定的内部支架蛋白，而空颗粒含有这种蛋白质。这些结果表明，VP 3是一种支架蛋白，分离的含VP 3的颗粒最有可能代表Chp 2前衣壳。
Chlamydiaphage Chp2 is a member of the family Microviridae, of which bacteriophage phiX174 is the type species. Although grouped in the same family, the relationship between the Microviridae coliphages and the Chp2-like viruses, which infect obligate intracellular parasitic bacteria, is quite distant, with major differences in structural protein content and scaffolding protein dependence. To investigate the morphogenesis of Chp2, large particles were isolated from infected Chlamydophila abortus by equilibrium and rate zonal sedimentation. A monoclonal antibody that recognizes only assembled viral coat proteins was used in these detection assays. Thus, the detected particles represent virions and/or postcapsid formation assembly intermediates. Two distinct particle types were detected, differing in both protein and DNA content. Filled particles lacked VP3, the putative internal scaffolding protein, whereas empty particles contained this protein. These results indicate that VP3 is a scaffolding protein and that the isolated VP3-containing particles most likely represent Chp2 procapsids.