EPR of a novel high‐spin component in activated hydrogenase from Desulfovibrio vulgaris (Hildenborough)

FEBS Letters

van Berkel-Arts, A.²  Krüse-Wolters, K.M.²  Dunham, W.R.¹  Veeger, C.²  Hagen, W.R.² 

[1] Biophysics Research Division, Institute of Science and Technology, The University of Michigan, Ann Arbor, MI 48109, USA;Department of Biochemistry, Agricultural University, De Dreijen 11, 6703 BC Wageningen, The Netherlands

关键词: Hydrogenase;    (Desulfovibrio vulgaris);    ESR;    Iron-sulfur cluster;   

DOI  :  10.1016/0014-5793(86)80590-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The EPR of reoxidized hydrogenase from Desulfovibrio vulgaris (H.) has been reinvestigated. In contrast to other workers [(1984) Proc. Natl. Acad. Sci. USA 81, 3728-3732] we find the axial signal with g = 2.06; 2.01 to be only a minor component of concentration 0.03 . In the spectrum of fully active reoxidized enzyme this signal is overshadowed by a rhombic signal (0.1 ) with g = 2.11; 2.05; 2.00 reminiscent of the only signal found for other oxidized bidirectional hydrogenases. In addition, a novel signal has been detected with g _eff = 5.0 which, under the assumptions that S = 2 and ¦Δm _s¦= 2, quantitates to roughly one . Ethylene glycol affects the relative intensity of the different signals. It is suggested that O₂ sensitization parallels a spin-state transition of an iron-sulfur cluster.

【 授权许可】

Unknown