Larsen R W, Chavez M D, Nunez D J, Davidson M W, Knaff D B, Krulwich T A, Ondrias M R
Department of Chemistry, University of New Mexico, Albuquerque 87131.
Arch Biochem Biophys. 1990 Dec;283(2):266-70. doi: 10.1016/0003-9861(90)90641-b.
The environment of the heme site of a low-potential soluble cytochrome (c552) from alkaliphilic Bacillus firmus RAB has been characterized with resonance Raman scattering and compared to that of horse heart cytochrome c. The Raman data indicate that vibrational bands sensitive to the axial ligation of the heme, as well as modes sensitive to the heme peripheral environment in cytochrome c552, are distinct from those of horse heart cytochrome c. The spectra of cytochrome c552 display resonance Raman modes indicative of a methionine as the sixth ligand in the oxidized form, while the reduced form appears to contain a nitrogenous-based sixth ligand. In addition, Q-band excitation reveals differences among vibrational modes in cytochrome c552 that are sensitive to the amino acid environment surrounding the heme.
利用共振拉曼散射对嗜碱芽孢杆菌RAB中低电位可溶性细胞色素（c552）血红素位点的环境进行了表征，并与马心细胞色素c的环境进行了比较。拉曼数据表明，对血红素轴向配体敏感的振动带以及对细胞色素c552中血红素周边环境敏感的模式与马心细胞色素c的不同。细胞色素c552的光谱显示出共振拉曼模式，表明甲硫氨酸是氧化形式的第六个配体，而还原形式似乎含有一个含氮的第六个配体。此外，Q波段激发揭示了细胞色素c552中对血红素周围氨基酸环境敏感的振动模式之间的差异。
