Blatny Janet Martha, Godager Linda, Lunde Merete, Nes Ingolf Figved
Laboratory of Microbial Gene Technology, Department of Chemistry and Biotechnology, Agricultural University of Norway, 1432 As, Norway.
Virology. 2004 Jan 5;318(1):231-44. doi: 10.1016/j.virol.2003.09.019.
Complete genome sequencing of the P335 temperate Lactococcus lactis bacteriophage phiLC3 (32, 172 bp) revealed fifty-one open reading frames (ORFs). Four ORFs did not show any homology to other proteins in the database and twenty-one ORFs were assigned a putative biological function. phiLC3 contained a unique replication module and orf201 was identified as the putative replication initiator protein-encoding gene. phiLC3 was closely related to the L. lactis r1t phage (73% DNA identity). Similarity was also shared with other lactococcal P335 phages and the Streptococcus pyogenes prophages 370.3, 8232.4 and 315.5 over the non-structural genes and the genes involved in DNA packaging/phage morphogenesis, respectively. phiLC3 contained small homologous regions distributed among lactococcal phages suggesting that these regions might be involved in mediating genetic exchange. Two regions of 30 and 32 bp were conserved among the streptococcal and lactococcal r1t-like phages. These two regions, as well as other homologous regions, were located at mosaic borders and close to putative transcriptional terminators indicating that such regions together might attract recombination. The conserved regions found among lactococcal and streptococcal phages might be used for identification of phages/prophages/prophage remnants in their hosts.
对温和型乳酸乳球菌噬菌体phiLC3(32,172 bp)进行全基因组测序,发现了51个开放阅读框(ORF)。其中4个ORF在数据库中与其他蛋白质没有任何同源性,21个ORF被赋予了推定的生物学功能。phiLC3包含一个独特的复制模块,orf201被鉴定为推定的复制起始蛋白编码基因。phiLC3与乳酸乳球菌r1t噬菌体密切相关(DNA同一性为73%)。在非结构基因以及分别参与DNA包装/噬菌体形态发生的基因方面,它与其他乳酸球菌P335噬菌体以及化脓性链球菌原噬菌体370.3、8232.4和315.5也具有相似性。phiLC3包含分布在乳酸球菌噬菌体中的小同源区域,表明这些区域可能参与介导基因交换。在链球菌和乳酸球菌r1t样噬菌体中,有两个30 bp和32 bp的区域是保守的。这两个区域以及其他同源区域位于镶嵌边界处且靠近推定的转录终止子,表明这些区域可能共同吸引重组。在乳酸球菌和链球菌噬菌体中发现的保守区域可用于鉴定其宿主中的噬菌体/原噬菌体/原噬菌体残余物。