1RTC

THE STRUCTURE OF RECOMBINANT RICIN A CHAIN AT 2.3 ANGSTROMS

1RTC の概要

• エントリーDOI: 10.2210/pdb1rtc/pdb
• 分子名称: RICIN (2 entities in total)
• 機能のキーワード: glycosidase
• 由来する生物種: Ricinus communis (castor bean)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 30067.95

構造登録者

Mlsna, D.,Monzingo, A.F.,Katzin, B.J.,Ernst, S.,Robertus, J.D. (登録日: 1992-10-29, 公開日: 1993-10-31, 最終更新日: 2024-02-14)

主引用文献

Mlsna, D.,Monzingo, A.F.,Katzin, B.J.,Ernst, S.,Robertus, J.D.
Structure of recombinant ricin A chain at 2.3 A.
Protein Sci., 2:429-435, 1993

PubMed Abstract: The plant cytotoxin ricin is a heterodimer with a cell surface binding (B) chain and an enzymatically active A chain (RTA) known to act as a specific N-glycosidase. RTA must be separated from B chain to attack rRNA. The X-ray structure of ricin has been solved recently; here we report the structure of the isolated A chain expressed from a clone in Escherichia coli. This structure of wild-type rRTA has and will continue to serve as the parent compound for difference Fouriers used to assess the structure of site-directed mutants designed to analyze the mechanism of this medically and commercially important toxin. The structure of the recombinant protein, rRTA, is virtually identical to that seen previously for A chain in the heterodimeric toxin. Some minor conformational changes due to interactions with B chain and to crystal packing differences are described. Perhaps the most significant difference is the presence in rRTA of an additional active site water. This molecule is positioned to act as the ultimate nucleophile in the depurination reaction mechanism proposed by Monzingo and Robertus (1992, J. Mol. Biol. 227, 1136-1145).

PubMed: 8453380

実験手法

X-RAY DIFFRACTION (2.3 Å)