Two minimal Tat translocases in Bacillus
Two minimal Tat translocases in Bacillus
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DOI：
10.1111/j.1365-2958.2004.04341.x
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发表时间：
2004-12-01
影响因子：
3.6
通讯作者：
van Dijl, JM
中科院分区：
文献类型：
--
作者：
Jongbloed, JDH;Grieger, U;van Dijl, JM
达特机器的蛋白质运输跨内膜的大肠杆菌和叶绿体类囊体膜的活动需要三种膜蛋白的存在：TatA，TatB和TatC。在这里，我们表明，达特机制的革兰氏阳性细菌枯草芽孢杆菌是非常不同的，因为它包含至少两个最小的达特易位酶，每个组成的一个特定的TatA和一个特定的TatC组件。第三，TatB类组件显然是不需要的。这意味着B. subtilis同时具有E. coli和类囊体。值得注意的是，两个B。命名为TatAdCd和TatAyCy的枯草杆菌易位酶都分别作为双精氨酸前蛋白PhoD和YwbN的单独的底物特异性易位酶起作用。重要的是，这些最小的B.枯草芽孢杆菌是绝大多数革兰氏阳性细菌的达特机制的代表，链霉菌是唯一已知的具有TatABC易位酶的例外。
Activity of the Tat machinery for protein transport across the inner membrane of Escherichia coli and the chloroplast thylakoidal membrane requires the presence of three membrane proteins: TatA, TatB and TatC. Here, we show that the Tat machinery of the Gram-positive bacterium Bacillus subtilis is very different because it contains at least two minimal Tat translocases, each composed of one specific TatA and one specific TatC component. A third, TatB-like component is apparently not required. This implies that TatA proteins of B. subtilis perform the functions of both TatA and TatB of E. coli and thylakoids. Notably, the two B. subtilis translocases named TatAdCd and TatAyCy both function as individual, substrate-specific translocases for the twin-arginine preproteins PhoD and YwbN, respectively. Importantly, these minimal TatAC translocases of B. subtilis are representative for the Tat machinery of the vast majority of Gram-positive bacteria, Streptomycetes being the only known exception with TatABC translocases.