Photosensitive nitrile hydratase intrinsically possesses nitric oxide bound to the non‐heme iron center: evidence by Fourier transform infrared spectroscopy

[摘要]

Nitrile hydratase (NHase) from Rhodococcus sp. N771 is a photosensitive enzyme that catalyzes hydration of nitriles to the corresponding amides. Light-induced Fourier transform infrared difference spectra between the inactive and active forms of NHase were measured with both the natural (¹⁴N) and ¹⁵N-labeled NHases. The results showed, for the first time, that NHase intrinsically possesses nitric oxide (NO) molecules bound to the non-heme iron center. The possible role of NO in the photoactivation process of NHase is discussed.

[学科分类] 生物化学/生物物理

[关键词] Nitric oxide;Nitrile hydratase;Fourier transform infrared spectroscopy;Non-heme iron;Photoactivation;ENDOR;electron nuclear double resonance;EPR;electron paramagnetic resonance;EXAFS;extended X-ray absorption fine structure;FTIR;Fourier transform infrared;NHase;nitrite hydratase;NOS;nitrite oxide synthase