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PubMed · 11293544

Fe-type nitrile hydratase.

I Endo·M Nojiri·M Tsujimura·M Nakasako·S Nagashima·M Yohda·M Odaka
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Abstract

The characteristic features of Fe-type nitrile hydratase (NHase) from Rhodococcus sp. N-771 are described. Through the biochemical analyses, we have found that nitric oxide (NO) regulates the photoreactivity of this enzyme by association with the non-heme iron center and photoinduced dissociation from it. The regulation is realized by a unique structure of the catalytic non-heme iron center composed of post-translationally modified cysteine-sulfinic (Cys-SO2H) and -sulfenic acids (Cys-SOH). To understand the biogenic mechanism and the functional role of these modifications, we constructed an over-expression system of whole NHase and individual subunits in Escherichia coli. The results of the studies on several recombinant NHases have shown that the Cys-SO2H oxidation of alphaC112 is indispensable for the catalytic activity of Fe-type NHase.

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Binding SitesHydro-LyasesIronModels, MolecularProtein ConformationRecombinant ProteinsRhodococcusJournal ArticleResearch Support, Non-U.S. Gov'tReview

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I Endo, M Nojiri, M Tsujimura, M Nakasako, S Nagashima, M Yohda, M Odaka. 2001. Fe-type nitrile hydratase.. https://doi.org/10.1016/s0162-0134(00)00171-9

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