Fe-type nitrile hydratase.
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.
Endo
I
I
Biochemical Systems Laboratory, The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama, Japan. endo@cel.riken.go.jp
Nojiri
M
M
Tsujimura
M
M
Nakasako
M
M
Nagashima
S
S
Yohda
M
M
Odaka
M
M
D001665:Binding Sites; D006836:Hydro-Lyases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D007501:Iron / Q000378:metabolism*; D008958:Models, Molecular; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012240:Rhodococcus / Q000201:enzymology* / Q000235:genetics
D011994:Recombinant Proteins; D007501:Iron; D006836:Hydro-Lyases; C048831:nitrile hydratase