Banci L, Bertini I, Kuan I C, Tien M, Turano P, Vila A J
Department of Chemistry, University of Florence, Italy.
Biochemistry. 1993 Dec 14;32(49):13483-9. doi: 10.1021/bi00212a013.
The 1H NMR spectroscopy was used to study lignin peroxidase (LiP) and manganese peroxidase (MnP) containing deuterated histidines. LiP and MnP were obtained from a histidine auxotroph of the fungus Phanerochaete chrysosporium grown in the presence of deuterated histidines. The derivatives with deuterated histidines have allowed a firm assignment of the protons of the distal and proximal histidines. We have also found that the LiP from this strain exhibits different orientations of the 2-vinyl group compared to the LiP from the strain previously studied. Mobility of the group has also been detected, thus explaining the apparent inconsistency between X-ray solid-state and NMR solution data. The 15N shift values of 15N-enriched CN- in the cyanide derivatives of LiP and MnP have also been measured. The shift patterns, both for 15N and for the proximal histidine protons of several peroxidases, are consistent with predominant contact shift contributions which reflect the bond strength of the metal-axial ligand. Finally, our results confirm a correlation between shift values of 15N and those of proximal histidine protons and the Fe3+/Fe2+ redox potentials.
采用1H核磁共振光谱法研究了含有氘代组氨酸的木质素过氧化物酶（LiP）和锰过氧化物酶（MnP）。LiP和MnP是从在氘代组氨酸存在下生长的真菌黄孢原毛平革菌的组氨酸营养缺陷型菌株中获得的。含有氘代组氨酸的衍生物使得能够明确归属远端和近端组氨酸的质子。我们还发现，与之前研究的菌株来源的LiP相比，该菌株来源的LiP的2-乙烯基具有不同的取向。还检测到了该基团的流动性，从而解释了X射线固态数据和核磁共振溶液数据之间明显的不一致。还测量了LiP和MnP的氰化物衍生物中15N富集的CN-的15N位移值。几种过氧化物酶的15N以及近端组氨酸质子的位移模式与主要的接触位移贡献一致，这反映了金属-轴向配体的键强。最后，我们的结果证实了15N的位移值与近端组氨酸质子的位移值以及Fe3+/Fe2+氧化还原电位之间存在相关性。
