Sokolova O S, Shaburova O V, Pechnikova E V, Shaytan A K, Krylov S V, Kiselev N A, Krylov V N
M.V. Lomonosov Moscow State University, Moscow, Russia; A.V. Shoubnikov Institute of Crystallography RAS, Moscow, Russia.
I.I. Mechnikov Research Institute of Vaccines and Sera, RAMS, Moscow, Russia.
Virology. 2014 Nov;468-470:472-478. doi: 10.1016/j.virol.2014.09.002. Epub 2014 Sep 22.
A unique feature of the Pseudomonas aeruginosa giant phage phiKZ is its way of genome packaging onto a spool-like protein structure, the inner body. Until recently, no similar structures have been detected in other phages. We have studied DNA packaging in P. aeruginosa phages EL and Lin68 using cryo-electron microscopy and revealed the presence of inner bodies. The shape and positioning of the inner body and the density of the DNA packaging in EL are different from those found in phiKZ and Lin68. This internal organization explains how the shorter EL genome is packed into a large EL capsid, which has the same external dimensions as the capsids of phiKZ and Lin68. The similarity in the structural organization in EL and other phiKZ-like phages indicates that EL is phylogenetically related to other phiKZ-like phages, and, despite the lack of detectable DNA homology, EL, phiKZ, and Lin68 descend from a common ancestor.
铜绿假单胞菌巨型噬菌体phiKZ的一个独特特征是其将基因组包装到一种卷轴状蛋白质结构——内体上的方式。直到最近，在其他噬菌体中尚未检测到类似结构。我们利用冷冻电子显微镜研究了铜绿假单胞菌噬菌体EL和Lin68中的DNA包装，并揭示了内体的存在。EL内体的形状、定位以及DNA包装密度与phiKZ和Lin68中的不同。这种内部结构解释了较短的EL基因组是如何被包装到一个大型EL衣壳中的，该衣壳的外部尺寸与phiKZ和Lin68的衣壳相同。EL与其他phiKZ样噬菌体在结构组织上的相似性表明，EL在系统发育上与其他phiKZ样噬菌体相关，并且，尽管缺乏可检测到的DNA同源性，但EL、phiKZ和Lin68都起源于一个共同的祖先。
