Casjens Sherwood R
Division of Cell Biology and Immunology, Department of Pathology, University of Utah Medical School, Salt Lake City, UT 84132, USA.
Curr Opin Microbiol. 2005 Aug;8(4):451-8. doi: 10.1016/j.mib.2005.06.014.
The number of completely sequenced tailed-bacteriophage genomes that have been published increased to more than 125 last year. The comparison of these genomes has brought their highly mosaic nature into much sharper focus. Furthermore, reports of the complete sequences of about 150 bacterial genomes have shown that the many prophage and parts thereof that reside in these bacterial genomes must comprise a significant fraction of Earth's phage gene pool. These phage and prophage genomes are fertile ground for attempts to deduce the nature of viral evolutionary processes, and such analyses have made it clear that these phage have enjoyed a significant level of horizontal exchange of genetic information throughout their long histories. The strength of these evolutionary deductions rests largely on the extensive knowledge that has accumulated during intensive study into the molecular nature of the life cycles of a few 'model system' phages over the past half century. Recent molecular studies of phages other than these model system phages have made it clear that much remains to be learnt about the variety of lifestyle strategies utilized by the tailed-phage.
去年，已发表的完全测序的有尾噬菌体基因组数量增加到了125个以上。对这些基因组的比较使其高度嵌合的性质更加清晰地显现出来。此外，约150个细菌基因组的全序列报告表明，存在于这些细菌基因组中的许多原噬菌体及其部分必定构成了地球噬菌体基因库的很大一部分。这些噬菌体和原噬菌体基因组是推断病毒进化过程本质的丰富素材，此类分析已明确表明，这些噬菌体在其漫长的历史中经历了显著水平的遗传信息横向交换。这些进化推断的力度很大程度上依赖于在过去半个世纪对少数“模型系统”噬菌体生命周期的分子本质进行深入研究过程中积累的广泛知识。最近对这些模型系统噬菌体以外的噬菌体进行的分子研究表明，关于有尾噬菌体所采用的各种生活方式策略，仍有许多有待了解。
