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Updated: Jun 20, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Structural basis for catalytic activation of thiocyanate hydrolase involving metal-ligated cysteine modification
Takatoshi Arakawa1, Yoshiaki Kawano, Yoko Katayama
1Department of Biotechnology and Life Science, Graduate School of Technology, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
Abstract:
Thiocyanate hydrolase (SCNase) is a member of a family of nitrile hydratase proteins, each of which contains a unique noncorrin cobalt center with two post-translationally modified cysteine ligands, cysteine-sulfenic acid or -sulfenate (Cys-SO(H)), and cysteine-sulfininate (Cys-SO(2)(-)), respectively. We have found that a partially matured recombinant SCNase was activated during storage. The crystal structures of SCNase before and after storage demonstrated that Cys-SO(2)(-) modification of gammaCys131 proceeded to completion prior to storage, while Cys-SO(H) modification of gammaCys133 occurred during storage. SCNase activity was suppressed when gammaCys133 was further oxidized to Cys-SO(2)(-). The correlation between the catalytic activity and the extent of the gammaCys133 modification indicates that the cysteine sulfenic acid modification of gammaCys133 is of primary importance in determining the activity of SCNase.
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