Casjens Sherwood R, Gilcrease Eddie B
Division of Cell Biology and Immunology, Department of Pathology, University of Utah Medical School, Salt Lake City, UT, USA.
Methods Mol Biol. 2009;502:91-111. doi: 10.1007/978-1-60327-565-1_7.
Tailed-bacteriophage virions contain a single linear dsDNA chromosome which can range in size from about 18 to 500 kbp across the known tailed-phage types. These linear chromosomes can have one of several known types of termini as follows: cohesive ends (5'- or 3'-single-strand extensions), circularly permuted direct terminal repeats, short or long exact direct terminal repeats, terminal host DNA sequences, or covalently bound terminal proteins. These different types of ends reflect differing DNA replication strategies and especially differing terminase actions during DNA packaging. In general, complete genome sequence determination does not by itself elucidate the nature of these ends, so directed experimental analysis is usually required to understand the nature of the virion chromosome ends. This chapter discusses these methods.
有尾噬菌体病毒粒子包含一条单一的线性双链DNA染色体，在已知的有尾噬菌体类型中，其大小范围约为18至500千碱基对。这些线性染色体可以有以下几种已知类型的末端之一：粘性末端（5'-或3'-单链延伸）、环状排列的直接末端重复序列、短或长的精确直接末端重复序列、末端宿主DNA序列或共价结合的末端蛋白。这些不同类型的末端反映了不同的DNA复制策略，尤其是在DNA包装过程中不同的末端酶作用。一般来说，完整的基因组序列测定本身并不能阐明这些末端的性质，因此通常需要进行定向实验分析来了解病毒粒子染色体末端的性质。本章将讨论这些方法。
