A Vibrio cholerae pathogenicity island associated with epidemic and pandemic strains
A Vibrio cholerae pathogenicity island associated with epidemic and pandemic strains
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DOI：
10.1073/pnas.95.6.3134
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发表时间：
1998-03-17
影响因子：
11.1
通讯作者：
Reeves, PR
中科院分区：
文献类型：
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作者：
Karaolis, DKR;Johnson, JA;Reeves, PR
霍乱弧菌包括无害的水生菌株以及能够引起霍乱流行和全球大流行的菌株。在研究致病性和非致病性菌株之间的关系时，我们发现了一个染色体致病岛（派），该岛存在于流行病和大流行菌株中，但在非致病性菌株中不存在。最初，两个ToxR调控基因（aldA和tagA）进行了研究，并发现与流行和大流行菌株，但在非致病菌株缺席。含有aldA和tagA的区域包含13 kb的先前未鉴定的DNA，并且是派的一部分，PAI含有毒力基因（ToxT）的调节子和编码必需的定植因子和霍乱毒素噬菌体受体（毒素共调节菌毛; TCP）的基因簇。派的大小为39.5 kb，具有低%G+C（35%），含有推定的整合酶和转座酶基因，两侧是att位点，并插入10 Sa RNA基因（ssrA）附近，这表明它可能是噬菌体起源。我们在两个临床非O 1/非O 139霍乱毒素阳性菌株中发现了这种派，这表明它可以在霍乱弧菌内转移。该派内的序列包括与致病性大肠杆菌的IV型菌毛基因簇相关的基因具有同源性的ORF、来自鳗弧菌的转座酶和几个不具有已知同源性的ORF。由于派含有CTX Phi受体，因此它可能是流行性和大流行性霍乱出现所需的初始遗传因子。我们建议将这个岛称为VPI（霍乱弧菌致病岛）。
The bacterial species Vibrio cholerae includes harmless aquatic strains as well as strains capable of causing epidemics and global pandemics of cholera. While investigating the relationship between pathogenic and nonpathogenic strains, we identified a chromosomal pathogenicity island (PAI) that is present in epidemic and pandemic strains but absent from nonpathogenic strains. Initially, two ToxR-regulated genes (aldA and tagA) were studied and were found to be associated with epidemic and pandemic strains but absent in nontoxigenic strains. The region containing aldA and tagA comprises 13 kb of previously unidentified DNA and is part of a PAI that contains a regulator of virulence genes (ToxT) and a gene cluster encoding an essential colonization factor and the cholera toxin phage receptor (toxin-coregulated pilus; TCP). The PAI is 39.5 kb in size, has low %G+C (35%), contains putative integrase and transposase genes, is flanked by att sites, and inserts near a 10Sa RNA gene (ssrA), suggesting it may be of bacteriophage origin. We found this PAI in two clinical non-O1/non-O139 cholera toxin-positive strains, suggesting that it can be transferred within V. cholerae. The sequence within this PAI includes an ORF with homology to a gene associated with the type IV pilus gene cluster of enteropathogenic Escherichia coli, a transposase from Vibrio anguillarum, and several ORFs with no known homology. As the PAI contains the CTX Phi receptor, it may represent the initial genetic factor required for the emergence of epidemic and pandemic cholera. We propose to call this island VPI (V. cholerae pathogenicity island).