Molecular genetic analysis of the evolution of cytotoxin-converting phages and the horizontal transfer of toxin genes.

细胞毒素转化噬菌体进化和毒素基因水平转移的分子遗传学分析。

• 批准号: 09670277
• 负责人: HAYASHI Tetsuya
• 金额: $ 2.05万
• 依托单位: Shinshu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09670277/
• 关键词: bacteriophage; genome structure; molecular evolution; bacteriocin; horizontal gene transfer; toxin gene; サイトトキシン; 溶菌遺伝子; ゲノムシークエンス

φCTX is a cytotoxin-converting phage isolated from Pseudomons aeruginosa. In this study, we determined the complete nucleotide sequence of φCTX phage genome. The precise genome size was 35,538 bp. Forty seven ORFs were identified on the φCTX genome, including two previously identified genes, ctx and int. Among them, fifteen gene products were identified in the phage particle. The most striking feature of the φCTX genome was an extensive homology with the coliphage P2 and P2-related phages; more than half of the ORFs had marked homology to P2 genes. The gene arrangement on the genome was also highly conserved for the two phages, though the G+C content and codon usage of most φCTX genes were similar to those of the host P. aeruginosa chromosome. In addition, φCTX was found to share several common features with P2, including the morphology, non-inducibility, use of LPS core oligosaccharide as receptor and CaィイD22+ィエD2-dependent receptor binding. These findings indicate that φCTX is a P2-l … More ike phage well adapted to P. aeruginosa, and provide a clear evidence of the intergeneric spread and evolution of bacteriophages. Furthermore, comparative analysis of genome structures of φCTX, P2 and other P2-relatives revealed the presence of several hot spots where foreign DNAs, including the cytotoxin gene, were inserted. They appear to be deeply concerned in the acquisition of various genes that are horizontally transferred by bacteriophage infection.Pseudomonas aeruginosa produces three types of bacteriocins; R-type, F-type, and S-type pyocins. The S-type pyocin is a simple colicin-like protein, whereas the R-type resembles a contractile tail structure of bacteriophage, and the F-type a non-contractile tail of bacteriophage. Since φCTX is a member of R pyocin-related phages which are genetically and serologically related to R pyocin, above-mentioned results suggested the relatedness of R pyocin to the P2 phage family. Thus, the nucleotide sequence of R2 pyocin genes, along with those for F2 pyocin which are located downstream of the R2 gene cluster on the chromosome of P. aeruginosa PAO1, was analyzed in order to elucidate the relationship between the pyocins and bacteriophages. Further, in order to specify the R2 pyocin locus, we determined the nucleotide sequence of the corresponding region of the strain PML14 which produced only F2 pyocin. The results clearly demonstrated that the R-type pyocin is derived from a common ancestral origin with the P2 phage family and the F-type from the λ phage family. This notion was supported by identification of a lysis gene cassette similar to those for bacteriophages. The gene organization of the R2 and F2 pyocin gene cluster, however, suggested that the both pyocins are not simple defective phages but are phage tails that have been evolutionarily specialized as bacteriocins. Less

φCTX是一种从铜绿假子分离的细胞毒素转化噬菌体。在这项研究中，我们确定了φCTX噬菌体基因组的完整核苷酸序列。精确的基因组大小为35,538 bp。在φCTX基因组上鉴定了47个ORF，包括两个先前鉴定的基因CTX和INT。其中，在噬菌体颗粒中鉴定出15个基因产物。 φCTX基因组最引人注目的特征是与Coliphage P2和P2相关噬菌体的广泛同源性。超过一半的ORF与P2基因具有同源性。基因组上的基因排列在这两个噬菌体上也高度保守，尽管大多数φCTX基因的G+C含量和密码子使用与宿主铜绿假单胞菌染色体相似。此外，发现φCTX与P2共享几个共同特征，包括形态，不可诱导性，使用LPS核心寡糖作为受体和CAII D22+E D2依赖性受体结合。这些发现表明，φCTX是P2-L…更多地适应铜绿假单胞菌的IKE噬菌体，并提供了细菌间植物间扩散和进化的明确证据。此外，对φCTX，P2和其他P2含量的基因组结构的比较分析表明，存在几个热点，其中插入了包括细胞毒素基因在内的外源DNA。它们似乎深深关注的是通过细菌感染水平转移的各种基因的获取。铜绿假单胞菌产生三种类型的细菌蛋白。 R型，F-Type和S型上Pyocin。 S型上酸是一种简单的类菌蛋白样蛋白，而R型类似于噬菌体的收缩尾巴结构，而F型噬菌体的非收缩尾巴则是。由于φCTX是R Pyocin相关噬菌体的成员，这些噬菌体在遗传和血清学上与R Pyocin相关，因此上述结果表明R Pyocin与P2噬菌体家族的相关性。为了阐明铜绿假单胞菌PAO1的染色体，R2加为毒素基因的核苷酸序列以及位于R2基因簇的下游的F2 pyocin的核苷酸序列，以阐明铜绿假单胞菌PAO1的染色体上的核苷酸序列，以阐明脓毒症和细菌之间的关系。此外，为了指定R2上加载菌素基因座，我们确定了仅产生F2 pyocin的菌株PML14相应区域的核苷酸序列。结果清楚地表明，R型上氧蛋白是由P2噬菌体家族和λ噬菌体家族的F型衍生出来的。通过鉴定类似于细菌的裂解基因盒子来支持该概念。然而，R2和F2上加载菌基因簇的基因组织表明，两种化脓素不是简单的缺陷噬菌体，而是噬菌体尾巴，而噬菌体尾巴已被进化化为细菌素。较少的

项目成果

Keisuke Nakayama: "The complete nucleotide sequencing of φctx, a cytotoxin-corverting phage of Pseudmonas aeruginouse : implzcations for phage evolution and horizontal gene transter via bacteriophages." Molecular Microbiology. 31. 399-419 (1999)

Keisuke Nakayama：“绿脓杆菌细胞毒素转化噬菌体 φctx 的完整核苷酸测序：通过噬菌体进行噬菌体进化和水平基因转移的意义”31. 399-419 (1999)。

Keisuke Nakayama: "The complete nucleotide sequence of φCTX, a cytotoxin-converting phage of Psendomonas aeruginosa : implications for phage evolution and horizontal gene transfer via bacteriophages"Molecular Microbiology. 31. 399-419 (1999)

Keisuke Nakayama：“铜绿假单胞菌的细胞毒素转化噬菌体 φCTX 的完整核苷酸序列：对噬菌体进化和通过噬菌体的水平基因转移的影响”《分子微生物学》31. 399-419 (1999)。

林 哲也: "現代医学の基礎第11巻 感染と生体防御(竹田美文、渡辺武;編) 第5章 病原細菌のゲノム解析(第11巻第5章)"岩波書店. 248(19) (2000)

Tetsuya Hayashi：“现代医学基础第 11 卷：感染和生物防御（武田义文、渡边毅编辑）第 5 章：病原菌的基因组分析（第 11 卷第 5 章）”岩波书店 248(19)（2000 年）。 ）

K. Nakayama et al.: "The complete nucleotide sequence of φCTX, a cytotoxin-converting phage of psendomonas aeruginosa implications for phage evolution and horizontal gene transfer via bacteriophages"Molecular Microbiology. 31. 399-419 (1999)

K. Nakayama 等人：“铜绿假单胞菌的细胞毒素转化噬菌体 φCTX 的完整核苷酸序列对噬菌体进化和通过噬菌体进行水平基因转移的影响”《分子微生物学》31. 399-419 (1999)。

Keisuke Nakayama: "The complete nucleotide sequence of φCTX, a cytotoxin-converting phage of Pseudomonas aerrginosa:implieations for phage enolution and horizontal gene transter via bacteriophage"Molecular Microbiology. 31. 399-419 (1999)

Keisuke Nakayama：“铜绿假单胞菌的细胞毒素转化噬菌体 φCTX 的完整核苷酸序列：通过噬菌体进行噬菌体洗脱和水平基因转移的含义”《分子微生物学》31. 399-419 (1999)。