摘要
我们研究了血红素C+-肽含氰络合物的共振喇曼光谱。我们的实验结果证明,氰化物可以很高的亲和力与血红素C+-肽生成低自旋三价铁的络合物其Fe(Ⅲ)-CN^-伸缩振动频率为462cm^(-1),它比血红素C+-肽一氧化碳络合物中的Fe(Ⅱ)-CO伸缩振动频率509cm^(-1)要低47cm^(-1)
Heme C undecapeptide is a protolytic fragment of horse heart ferricytochrome C from residue 11-21 (H11) containig the covalently bonded heme and the intrinsic histidine. Cyanide ion binds to heme C undecapeptide with a very high affinity to form low-spin iron (Ⅲ) complexes. The Fe(Ⅲ)-CN^- stretching frequency and the bound CN stretching fre- quency in cyanoment heme C undecapeptide were detected at 462 CM^(-1) and 2082 CM^(-1). The v (Fe(Ⅲ)-CN^-) observed at 462cm^(-1) is 47 CM^(-1) lower than the v(Ⅲ)-CO) frequency at 509 CM^(-1). There indicated that the pair elec- trons of both CN- and CO ligands coordinate to the d_z^2 orbital to form a σ bond. But there may be greater π bonding between dπ (Fe) and π* (CO).
出处
《光散射学报》
1991年第1期63-69,共7页
The Journal of Light Scattering
关键词
血红素C十一肽
含氰络合物
散射谱
Cyanomet Heme C undecapeptide Raman Spectra and Heme C undecapeptide
