Escherichia coli cytidine deaminase provides a molecular model for ApoB RNA editing and a mechanism for RNA substrate recognition
Escherichia coli cytidine deaminase provides a molecular model for ApoB RNA editing and a mechanism for RNA substrate recognition
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DOI：
10.1006/jmbi.1997.1506
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发表时间：
1998-01-30
影响因子：
5.6
通讯作者：
Scott, J
中科院分区：
文献类型：
--
作者：
Navaratnam, N;Fujino, T;Scott, J
载脂蛋白rna编辑酶（apobec1）是一种胞苷脱氨酶。分子模拟和诱变表明，apobec1在四级和三级结构上与大肠杆菌胞苷脱氨酶（ecccda）相关。这两种酶形成同型二聚体，其复合活性位点由每个单体的贡献组成。与ECCDA相比，apobec1序列存在显著的间隙。间隙的总质量（10 kDa）与最小RNA底物的质量相匹配。它们在ECCDA中的位置表明abobec1如何重塑以适应RNA底物。在该模型中，与下游U的一个活性位点（相当于脱氨产物）的不对称结合有助于靶向上游C底物的另一个活性位点进行脱氨。(C) 1998学术出版社有限公司
ApoB RNA-editing enzyme (APOBEC-1) is a cytidine deaminase. Molecular modeling and mutagenesis show that APOBEC-1 is related in quaternary and tertiary structure to Escherichia coli cytidine deaminase (ECCDA). Both enzymes form a homodimer with composite active sites constructed with contributions from each monomer. Significant gaps are present in the APOBEC-1 sequence, compared to ECCDA. The combined mass of the gaps (10 kDa) matches that for the minimal RNA substrate. Their location in ECCDA suggests how ABOBEC-1 can be reshaped to accommodate an RNA substrate. In this model, the asymmetrical binding to one active site of a downstream U (equivalent to the deamination product) helps target the other active site for deamination of the upstream C substrate. (C) 1998 Academic Press Limited.