The 2.5 A structure of pokeweed antiviral protein.
The 2.5 A structure of pokeweed antiviral protein.
复制标题
美洲商陆抗病毒蛋白的2.5A结构。
DOI：
10.1006/jmbi.1993.1547
复制
发表时间：
1993
影响因子：
5.6
通讯作者：
J. Robertus
中科院分区：
文献类型：
--
作者：
A. Monzingo;E. Collins;S. Ernst;J. Irvin;J. Robertus
The pokeweed antiviral protein (PAP), isolated from the leaves of Phytolacca americana, is one of a family of plant and bacterial ribosome-inhibiting proteins (RIPs) which act as specific N-glycosidases on rRNA. Here we report the three-dimensional structure of PAP determined to 2.5 A resolution by X-ray crystallography. After 14 rounds of refinement, the R factor is 0.17 for 5.0 to 2.5 A data. The protein is homologous with the A chain of ricin and exhibits a very similar folding pattern. The positions of key active site residues are also similar. We also report the 2.8 A structure of PAP complexed with a substrate analog, formycin 5'-monophosphate. As seen previously in ricin, the formycin ring is stacked between invariant tyrosines 72 and 123. Arg179 bonds to N-3 which is thought to be important in catalysis.
