2PQG

Crystal structure of inactive ribosome inactivating protein from maize (b-32)

2PQG の概要

• エントリーDOI: 10.2210/pdb2pqg/pdb
• 分子名称: Ribosome-inactivating protein 3 (2 entities in total)
• 機能のキーワード: pro-rip, ribosome inactivating protein, maize, hydrolase
• 由来する生物種: Zea mays
• 細胞内の位置: Cytoplasm: P25891
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 59214.02

構造登録者

Mak, A.N.S.,Wong, Y.T.,Young, J.A.,Cha, S.S.,Sze, K.H.,Au, S.W.N.,Wong, K.B.,Shaw, P.C. (登録日: 2007-05-02, 公開日: 2008-02-19, 最終更新日: 2023-08-30)

主引用文献

Mak, A.N.,Wong, Y.T.,An, Y.J.,Cha, S.S.,Sze, K.H.,Au, S.W.,Wong, K.B.,Shaw, P.C.
Structure-function study of maize ribosome-inactivating protein: implications for the internal inactivation region and the sole glutamate in the active site.
Nucleic Acids Res., 35:6259-6267, 2007

PubMed Abstract: Maize ribosome-inactivating protein is classified as a class III or an atypical RNA N-glycosidase. It is synthesized as an inactive precursor with a 25-amino acid internal inactivation region, which is removed in the active form. As the first structural example of this class of proteins, crystals of the precursor and the active form were diffracted to 2.4 and 2.5 A, respectively. The two proteins are similar, with main chain root mean square deviation (RMSD) of 0.519. In the precursor, the inactivation region is found on the protein surface and consists of a flexible loop followed by a long alpha-helix. This region diminished both the interaction with ribosome and cytotoxicity, but not cellular uptake. Like bacterial ribosome-inactivating proteins, maize ribosome-inactivating protein does not have a back-up glutamate in the active site, which helps the protein to retain some activity if the catalytic glutamate is mutated. The structure reveals that the active site is too small to accommodate two glutamate residues. Our structure suggests that maize ribosome-inactivating protein may represent an intermediate product in the evolution of ribosome-inactivating proteins.

PubMed: 17855394
DOI: 10.1093/nar/gkm687

実験手法

X-RAY DIFFRACTION (2.38 Å)