Analysis of catalytic mechanism of a metalloenzyme, nitrile hydratase.
|
Accession number;04A0258623
|
| Title;Analysis of catalytic mechanism of a metalloenzyme, nitrile hydratase. |
| Author;
TANIGUCHI KAYOKO
(Inst. of Physical and Chemical Res.)
TSUJIMURA MASANARI
(Inst. of Physical and Chemical Res.)
ODAKA MASAFUMI
(Inst. of Physical and Chemical Res.)
HIROSE TAKUJI
(Saitama Univ., Graduate School, JPN)
ENDO ISAO
(Utsunomiya Univ., Fac. Agriculture, JPN)
MAEDA MIZUO
(Inst. of Physical and Chemical Res.)
|
Journal Title;Abstracts. Symposium on Biofunctional Chemistry
|
Journal Code:L0836A
|
ISSN:
|
|
VOL.18th;NO.;PAGE.82-83(2003)
|
| Figure&Table&Reference;FIG.3, REF.3 |
| Pub. Country;Japan |
| Language;Japanese |
| Abstract;Nitrile hydratase (NHase) catalyzes the hydration of nitriles to amides and is used for the industrial production of nicotinamide and acrylamide. However, the details of its catalytic mechanism remain unclear. In this study, we examined the interaction of Fe-type NHase and isovaleronitrile (IVN). Kinetic study suggested that NHase has a low catalytic activity and high affinity for IVN. This result was also supported by the fact that the UV-Vis absorption spectra of native NHase showed a large red-shift upon addition of IVN, and recovered to its original one within a few minutes. The UV-Vis spectra of NHase (dSO2H), however, red-shifted only when a large excess amount of IVN was added. This result suggested that the NHase (dSO2H) has a low affinity for IVN. On the other hand, NMR analysis showed that commercially-available IVN contained i-BuNC as an impurity. Actually, t-BuNC, one of the BuNC derivatives, also induced a red-shift in the absorption spectrum of NHase. These results strongly suggested that i-BuNC contained in IVN reagent affected the kinetic and spectral properties of NHase, and that this was a main reason for the contradictory results mentioned above. Furthermore, it was suggested that isocyanide compounds also interacted with NHase. (author abst.) |
|
|
|
Related Articles;
|
|
