Nicolaides Antonis, Soulimane Tewfik, Varotsis Constantinos
Cyprus University of Technology, Department of Environmental Science and Technology P. O. Box 50329 3603 Lemesos Cyprus
Chemical and Environmental Science Department, Materials & Surface Science Institute, University of Limerick Limerick Ireland.
RSC Adv. 2019 Feb 6;9(9):4776-4780. doi: 10.1039/c8ra09954e. eCollection 2019 Feb 5.
A reversible temperature-dependent high-spin to low-spin transition with = -60 °C has been observed in the resonance Raman spectra of the equilibrium reduced and photoreduced heme of the thermophilic heme-copper oxidoreductase. The transition is based on the frequency shifts of the spin-state marker bands (CC) and (CC) and is attributed to the displacement of the heme iron along the heme normal as a consequence of the Fe-Np repulsion at temperature below -40 °C which will increase the ligand field strength forcing the pairing of d electrons into the lower energy orbitals.
在嗜热血红素 - 铜氧化还原酶的平衡还原态和光还原态血红素的共振拉曼光谱中，观察到了一种可逆的、温度依赖性的高自旋到低自旋转变，转变温度(T_{1/2} = -60 °C)。这种转变基于自旋态标记带(v_4(CC))和(v_10(CC))的频率变化，并且归因于在温度低于(-40 °C)时，由于铁 - 近邻配体（Fe - Np）排斥导致血红素铁沿着血红素法线方向的位移，这将增加配体场强度，迫使d电子配对进入能量较低的轨道。
