VIRG, A PLASMID-CODED VIRULENCE GENE OF SHIGELLA-FLEXNERI - IDENTIFICATION OF THE VIRG PROTEIN AND DETERMINATION OF THE COMPLETE CODING SEQUENCE
VIRG, A PLASMID-CODED VIRULENCE GENE OF SHIGELLA-FLEXNERI - IDENTIFICATION OF THE VIRG PROTEIN AND DETERMINATION OF THE COMPLETE CODING SEQUENCE
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DOI：
10.1128/jb.171.1.353-359.1989
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发表时间：
1989-01-01
影响因子：
3.2
通讯作者：
YOSHIKAWA, M
中科院分区：
文献类型：
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作者：
LETT, MC;SASAKAWA, C;YOSHIKAWA, M
在福氏志贺菌2a株YSH 6000的230-内切酶对（kb）毒力质粒上，至少已鉴定出7个独立的遗传决定簇。其中之一，一个约4 kb的区域，virG，这是所需的Sereny反应，进行了广泛的研究，以检查virG区域的作用。在培养的MK细胞的细胞质中的YSH 6000的VirG-突变体（M94）的表型的特征在于通过侵袭志贺氏菌的动力学研究。在细胞质中观察到的M94表型表明virG基因座不是入侵志贺氏菌增殖所必需的，但对于它们向邻近细胞的扩散是必需的。VirG功能所必需的DNA区域定位于230-kb质粒上的3.6-kb DNA序列。证实了130千道尔顿的多肽是virG产物。用125 I对细菌进行外部标记表明，130千道尔顿的virG蛋白暴露在细菌表面。确定了包含功能性virG基因及其自身调控序列的4，472 bp的核苷酸序列，并鉴定了编码1，102个氨基酸残基的大开放阅读框。
On the 230-kilobase-pair (kb) virulence plasmid of Shigella flexneri 2a strain YSH6000, at least seven separate genetic determinants have been identified. One of them, an approximately 4-kb region, virG, that is required for the Sereny reaction, was extensively studied to examine the role of the virG region. The phenotype of a VirG- mutants (M94) of YSH6000 in the cytoplasm of cultured MK cells was characterized by a kinetic study of the invading shigellae. The observed phenotype of M94 in the cytoplasm indicated that the virG locus is not required for multiplication of the invading shigellae, but is essential for their spread to adjacent cells. The DNA regions neccessary for the VirG function was localized to a 3.6-kb DNA sequence on the 230-kb plasmid. A 130-kilodalton polypeptide was confirmed to be the virG product. External labeling of bacteria with 125I indicated that the 130-kilodalton virG protein is exposed on the bacterial surface. The nucleotide sequence of 4,472 bp, which contains the functional virG gene and its own regulatory sequence, was determined, and a large open reading frame encoding 1,102 amino acid residues was identified.