Crystal structure of Escherichia coli σE with the cytoplasmic domain of its anti-σ RseA
Crystal structure of Escherichia coli σE with the cytoplasmic domain of its anti-σ RseA
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DOI：
10.1016/s1097-2765(03)00148-5
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发表时间：
2003-04-01
期刊：
影响因子：
16
通讯作者：
Darst, SA
中科院分区：
文献类型：
--
作者：
Campbell, EA;Tupy, JL;Darst, SA
西格玛因子是细菌转录的关键调控因子。ECF(胞浆外功能)Sigma是Sigma(70)家族成员中规模最大、分歧最大的一组。ECF或‘s通常被其特定的抗Sigma因子隔离在不活跃的复合体中，该因子通常跨越内膜。在这里，我们测定了大肠杆菌ECF西格玛因子西格玛(E)的2埃分辨晶体结构，它与其抗西格玛的胞质结构域RseA形成了抑制性复合体。尽管存在广泛的序列变异，但sigma(E)的两个主要结构域在结构上实际上与其他sigma(70)家族成员的相应结构域相同。结合Sigma(E)全酶模型和生化数据，结构揭示了RseA通过空间封闭Sigma(E)上的两个核心RNA聚合酶结合决定簇发挥作用。
The sigma factors are the key regulators of bacterial transcription. ECF (extracytoplasmic function) sigma's are the largest and most divergent group of sigma(70) family members. ECF or's are normally sequestered in an inactive complex by their specific anti-sigma factor, which often spans the inner membrane. Here, we determined the 2 Angstrom resolution crystal structure of the Escherichia coli ECF sigma factor sigma(E) in an inhibitory complex with the cytoplasmic domain of its anti-sigma, RseA. Despite extensive sequence variability, the two major domains of sigma(E) are virtually identical in structure to the corresponding domains of other sigma(70) family members. In combination with a model of the sigma(E) holoenzyme and biochemical data, the structure reveals that RseA functions by sterically occluding the two primary binding determinants on sigma(E) for core RNA polymerase.