On the multicomponent nature of Halobacterium salinarum flagella
On the multicomponent nature of Halobacterium salinarum flagella
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DOI：
10.1134/s002626170704008x
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发表时间：
2007-08-01
期刊：
影响因子：
1.5
通讯作者：
Fedorov, O. V.
中科院分区：
文献类型：
--
作者：
Beznosov, S. N.;Pyatibratov, M. G.;Fedorov, O. V.
嗜盐古菌盐盐菌（Halobacterium salinarum）的鞭毛丝由5个鞭毛蛋白A1、A2、B1、B2和B3组成，这5个鞭毛蛋白由串联定位在两个flgA和flgB操纵子中的5个基因编码。虽然鞭毛蛋白A1和A2的作用已经确定，但B操纵子产物蛋白的作用仍不清楚。首次获得了一株缺失A、B鞭毛蛋白基因的盐芽孢杆菌（H. salinarum）突变株（Delta flgA）。该菌株已用于创建和分析仅携带单个B1或B3鞭毛蛋白基因的菌株。Delta flgA菌株的细胞具有7-8 nm厚的短丝状结构，我们将其命名为x丝。研究表明，x丝由一种与鞭毛蛋白a和b免疫相关的蛋白质组成。在缺乏A1、A2和B2的情况下，B1和B3基因的表达受到抑制。研究表明，鞭毛蛋白B1和B3在形成弯曲的钩状结构时不能取代鞭毛蛋白B2，后者是鞭毛细丝和马达轴之间的连接元件。除了提供运动外，鞭毛的多组分性质还讨论了它们可能参与其他细胞过程的可能性。
Filaments of the flagellum of the halophilic archaeon Halobacterium salinarum consist of five flagellins: A1, A2, B1, B2, and B3, which are encoded by five genes localized in tandem in two flgA and flgB operons. While the role of flagellins A1 and A2 has been determined, the role of the proteins, B operon products, is still unclear. A mutant strain of H. salinarum with deleted A and B flagellin genes (Delta flgA Delta flgB) has been obtained for the first time. This strain has been used to create and analyze the strains carrying only individual B1 or B3 flagellin genes. Cells of the Delta flgA Delta flgB strain were shown to have short filamentous formations, 7-8 nm thick, which we have named as X-filaments. It has been shown that X-filaments consist of a protein immunologically related to flagellins A and B. Expression of the B1 and B3 genes is suppressed in the absence of A1, A2, and B2. It has been shown that flagellins B1 and B3 cannot be substituted for flagellin B2 upon the formation of a curved hook-like structure, which serves as a connecting element between the flagellar filament and the motor axis. The multicomponent nature of flagella is discussed in the light of their possible involvement in other cell processes besides providing motility.