Formicka G, Zeppezauer M, Fey F, Hüttermann J
Department 12.4 Biochemistry, University of Saarland, Saarbruecken, Germany.
FEBS Lett. 1992 Aug 31;309(1):92-6. doi: 10.1016/0014-5793(92)80747-5.
Oxygen treatment of horse liver alcohol dehydrogenase EE isozyme substituted with Cu(II) at the catalytic site leads to bleaching with concomitant reduction to Cu(I) of approximately 90% of total Cu(II). The Cu(II) of the remaining 'minor species' cannot be reduced nor does it interact with exogenous ligands, e.g. 2-mercaptoethanol, imidazole, pyrazole, or azide ions. The EPR spectrum is axial with a super-hyperfine splitting of 15.6 G indicating binding of one nitrogen atom to Cu(II). These data as well as the energies and intensities of the absorption and CD spectra suggest the Cu(II) ion of the minor species to be located in the catalytic site of HLADH in a position and geometry different from that of the major species.
用铜（II）在催化位点取代的马肝乙醇脱氢酶EE同工酶进行氧气处理，会导致褪色，同时约90%的总铜（II）还原为铜（I）。其余“次要物种”的铜（II）无法被还原，也不与外源性配体相互作用，例如2-巯基乙醇、咪唑、吡唑或叠氮离子。电子顺磁共振光谱是轴向的，超精细分裂为15.6 G，表明有一个氮原子与铜（II）结合。这些数据以及吸收光谱和圆二色光谱的能量和强度表明，次要物种的铜（II）离子位于马肝乙醇脱氢酶的催化位点，其位置和几何形状与主要物种不同。
