Chen Chang-Lin, Pan Tzu-Ying, Kan Shu-Chen, Kuan Yi-Chia, Hong Lian-Yu, Chiu Kun-Ruei, Sheu Ching-Sen, Yang Jui-Sen, Hsu Wen-Hwei, Hu Hui-Yu
Institute of Molecular Biology, National Chung Hsing University, Taichung 402, Taiwan.
Virology. 2008 Sep 1;378(2):226-32. doi: 10.1016/j.virol.2008.05.027. Epub 2008 Jul 3.
P1201 is a lytic corynephage of Corynebacterium glutamicum NCHU 87078. Its genome consists of a linear double-stranded DNA molecule of 70,579 base pairs, with 3'-protruding cohesive ends of ten nucleotides. We have identified 69 putative open reading frames, including three apparent genes (thymidylate synthase, terminase, and RNR alpha subunit genes) that are interrupted by an intein. Protein-splicing activities of these inteins were demonstrated in Escherichia coli. Three structural proteins including major capsid and major tail proteins were separated by SDS-PAGE and identified by both LC-MS-MS and N-terminal sequence analyses. Bioinformatics analysis indicated that only about 8.7% of its putative gene products shared substantial protein sequence similarity with the lytic corynephage BFK20 from Brevibacterium flavum, the only corynephage whose genome had been sequenced to date, revealing that the P1201 genome is distinct from BFK20. The mosaic-like genome of P1201 indicates extensive horizontal gene transfer among P1201, Gordonia terrae phage GTE5, mycobacteriophages, and several regions of Corynebacterium spp. genomes.
P1201是谷氨酸棒杆菌NCHU 87078的一种裂解性棒状噬菌体。其基因组由一个70579个碱基对的线性双链DNA分子组成,具有10个核苷酸的3'突出粘性末端。我们鉴定出69个推定的开放阅读框,包括三个明显的基因(胸苷酸合成酶、末端酶和核糖核苷酸还原酶α亚基基因),这些基因被一个内含肽打断。这些内含肽的蛋白质剪接活性在大肠杆菌中得到了证实。通过SDS-PAGE分离出包括主要衣壳蛋白和主要尾蛋白在内的三种结构蛋白,并通过LC-MS-MS和N端序列分析进行了鉴定。生物信息学分析表明,其推定的基因产物中只有约8.7%与来自黄色短杆菌的裂解性棒状噬菌体BFK20具有实质性的蛋白质序列相似性,BFK20是迄今为止唯一其基因组已被测序的棒状噬菌体,这表明P1201基因组与BFK20不同。P1201的镶嵌样基因组表明在P1201、地戈登氏菌噬菌体GTE5、分枝杆菌噬菌体和棒状杆菌属基因组的几个区域之间存在广泛的水平基因转移。