Coupling protein stability and protein function in Escherichia coli CspA
Coupling protein stability and protein function in Escherichia coli CspA
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DOI：
10.1016/s1359-0278(98)00014-5
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发表时间：
1998-01-01
期刊：
影响因子：
--
通讯作者：
Gregoret, LM
中科院分区：
文献类型：
--
作者：
Hillier, BJ;Rodriguez, HM;Gregoret, LM
背景：CspA是一种结合单链RNA和DNA的小蛋白。CspA的结合位点由芳香族氨基酸簇组成，其在蛋白质表面上形成异常大的非极性斑块。由于非极性残基通常被发现在内部的蛋白质，这个集群可能已经发展到结合核酸的蛋白质stability.Results的费用：三个相邻的苯丙氨酸已突变单独和组合亮氨酸和丝氨酸。所有突变都会对DNA结合产生不利影响。令人惊讶的是，所有的突变，特别是那些丝氨酸，是disrupting.Conclusions：CspA中的芳香族簇不仅是蛋白质功能，但也为蛋白质的稳定性。这一结果对设计以芳香-芳香嵌入方式结合的P折叠蛋白和单链核酸结合蛋白具有一定的指导意义。
Background: CspA is a small protein that binds single-stranded RNA and DNA. The binding site of CspA consists of a cluster of aromatic amino acids, which form an unusually large nonpolar patch on the surface of the protein. Because nonpolar residues are generally found in the interiors of proteins, this cluster may have evolved to bind nucleic acids at the expense of protein stability.Results: Three neighboring phenylalanines have been mutated singly and in combination to leucine and to serine. All mutations adversely affect DNA binding. Surprisingly, all mutations, and especially those to serine, are destabilizing.Conclusions: The aromatic cluster in CspA is required not only for protein function but also for protein stability. This result is pertinent to the design of P-sheet proteins and single-stranded nucleic acid binding proteins, whose binding mode is proposed to be of aromatic-aromatic intercalation.