Küsthardt U, Hedman B, Hodgson K O, Hahn R, Vilter H
Lehrstuhl für Anorganische Chemie I, TU München, Garching, Germany.
FEBS Lett. 1993 Aug 23;329(1-2):5-8. doi: 10.1016/0014-5793(93)80180-3.
High-resolution X-ray absorption vanadium K-edge spectra were recorded for samples of vanadium-containing bromoperoxidase from the brown alga, Ascophyllum nodosum, at pH 9, 7, 5 and 4, as well as for enzyme samples containing the substrates, hydrogen peroxide and bromide. The well-resolved features of the XANES spectra are discussed. The pH-dependence of the structure of the active site has been studied revealing no significant change of the absorption features. We were able to detect an interaction of H2O2 with the vanadium site of the bromoperoxidase using XAS spectroscopy, whereas addition of bromide causes no energy shift of the XANES spectrum. The possible role of vanadium during the enzymatic reaction is discussed on the basis of our results.
在pH值为9、7、5和4的条件下，记录了来自褐藻泡叶藻的含钒溴过氧化物酶样品的高分辨率X射线吸收钒K边光谱，以及含有底物过氧化氢和溴化物的酶样品的光谱。讨论了XANES光谱中分辨良好的特征。研究了活性位点结构对pH的依赖性，结果表明吸收特征没有显著变化。我们能够利用XAS光谱检测到过氧化氢与溴过氧化物酶钒位点的相互作用，而添加溴化物不会导致XANES光谱发生能量偏移。根据我们的结果，讨论了钒在酶促反应中的可能作用。
