Photosensitivity of the Ni-A state of [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F with visible light

• Published in: Biochemical and biophysical research communications 2013-01, Vol.430 (1), p.284-288
• Main Authors: Osuka, Hisao, Shomura, Yasuhito, Komori, Hirofumi, Shibata, Naoki, Nagao, Satoshi, Higuchi, Yoshiki, Hirota, Shun
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; [NiFe] hydrogenase; DESULFOVIBRIO; Desulfovibrio vulgaris; Desulfovibrio vulgaris - enzymology; Desulfovibrio vulgaris Miyazaki F; E.S.R; ELECTRON SPIN RESONANCE; Enzymes; EPR; FOURIER TRANSFORMATION; FT-IR; G VALUE; Hydrogen; Hydrogenase; Hydrogenase - chemistry; Hydrogenase - radiation effects; HYDROGENASES; INFRARED SPECTRA; Iron - chemistry; IRRADIATION; Light; Light effects; Light sensitivity; Ni-A state; Nickel - chemistry; OXIDATION; Photochemical Processes; PHOTOSENSITIVITY; Redox properties; Spectroscopy, Fourier Transform Infrared; Temperature effects
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2012.10.136

► Ni-A state of [NiFe] hydrogenase showed light sensitivity. ► New FT-IR bands were observed with light irradiation of the Ni-A state. ► EPR g-values of the Ni-A state shifted upon light irradiation. ► The light-induced state converted back to the Ni-A state under the dark condition. [NiFe] hydrogenase catalyzes reversible oxidation of molecular hydrogen. Its active site is constructed of a hetero dinuclear Ni–Fe complex, and the oxidation state of the Ni ion changes according to the redox state of the enzyme. We found that the Ni-A state (an inactive unready, oxidized state) of [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F (DvMF) is light sensitive and forms a new state (Ni-AL) with irradiation of visible light. The Fourier transform infrared (FT-IR) bands at 1956, 2084 and 2094cm−1 of the Ni-A state shifted to 1971, 2086 and 2098cm−1 in the Ni-AL state. The g-values of gx=2.30, gy=2.23 and gz=2.01 for the signals in the electron paramagnetic resonance (EPR) spectrum of the Ni-A state at room temperature varied for −0.009, +0.012 and +0.010, respectively, upon light irradiation. The light-induced Ni-AL state converted back immediately to the Ni-A state under dark condition at room temperature. These results show that the coordination structure of the Fe site of the Ni-A state of [NiFe] hydrogenase is perturbed significantly by light irradiation with relatively small coordination change at the Ni site.