Resonance Raman spectra of blue copper proteins: assignments from normal mode calculations and copper-63/copper-65 and H2O/D2O shifts for stellacyanin and laccase
Resonance Raman spectra of blue copper proteins: assignments from normal mode calculations and copper-63/copper-65 and H2O/D2O shifts for stellacyanin and laccase
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蓝铜蛋白的共振拉曼光谱：星花青蛋白和漆酶的正常模式计算以及 Copper-63/copper-65 和 H2O/D2O 位移的分配
DOI：
10.1021/bi00301a008
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
T. Spiro
中科院分区：
文献类型：
--
作者：
L. Nestor;J. Larrabee;G. Woolery;B. Reinhammar;T. Spiro
放大图片作者：丽莎奈瑟，詹姆斯A. Larrabee，Geoffrey Woolery，Bengt Reinhammar和托马斯G. Spiro* 摘要：报告了天青蛋白、繁缕花青蛋白以及树木和真菌漆酶的共振拉曼（RR）光谱;注意到2型铜去除对漆酶RR光谱的影响。正常的坐标计算进行假设的铜配合物与已知的活性部位结构的质体蓝蛋白和天青蛋白通过使用从模型复合物转移的力常数的结构。在Cu-配体伸缩坐标中，仅Cu-S（Cys）伸缩对400-cm-1区域中的模式有显著贡献，在400-cm-1区域中发现最强的RR带; Cu-N（His）伸缩模式预计在230-310-cm-1范围内。Stellacyanin和树lacease已重建与63铜和65铜，并与D20，以评估铜和咪唑运动的RR模式。2-cm-1 D20/H20位移确定273-cm-1星花青苷RR带为Cu-N（His）模式;位移的程度表明C2以及N3咪唑质子被D取代。对于强的星花青苷或漆酶条带，观察到小得多的D20/H20位移。星花青苷的两个强RR带，347和385 cm-1，显示1.8-和1.5-cm-1的63 Cu/65 Cu同位素位移;组合位移是针对Cu-S（Cys）伸缩计算的位移。这表明这对带是由结合半胱氨酸的Cu-S伸缩和SCC弯曲坐标之间的强耦合引起的。平均频率比漆酶、天青蛋白和质体花青蛋白中强带的平均频率低约30 cm-1，这与星花青蛋白（2.19 nm）比质体花青蛋白或天青蛋白（2.13 nm）更长的扩展X射线吸收精细结构推导的Cu-S距离一致。然而，对于381、405和420 cm-1处的强带，漆酶63 Cu/65 Cu位移为0.5 cm-1或更小，远低于stel-lacyanin的位移，并且涉及额外的耦合。在300-500-cm-1区域中预期配位配体的各种角度弯曲模式，但难以解释它们中的大多数的共振增强。结果表明，半胱氨酸SC键的扭转运动对共振增强模有重要贡献.铜蛋白的蓝色或1型位点由于其不寻常的光谱性质而长期以来引起了人们极大的兴趣（Malkin & Malmstrom，1970; Fee，1975; Gray &所罗门，1981）。在过去的几年里，由于一系列物理方法的应用，包括吸收和圆二色性（CD）光谱学（McMillen et al.，1974 a，B;所罗门等人，1976 a，B）、核磁共振（NMR）光谱（Markley等，1975; Hill等人，1976; Ugerbil等人，1977），电子顺磁共振（EPR）光谱（Vanngard，1972），
Lisa Nestor, James A. Larrabee, Geoffrey Woolery, Bengt Reinhammar, and Thomas G. Spiro* abstract: Resonance Raman (RR) spectra are reported for azurin, stellacyanin, and both tree and fungal lacease; effects of type 2 Cu removal on the lacease RR spectra are noted. Normal coordinate calculations are carried out on hypothetical Cu complexes with structures related to the known active-site structure of plastocyanin and azurin by using force constants transferred from model complexes. Among the Cu-ligand stretching coordinates, only the Cu-S (Cys) stretch contributes significantly to modes in the 400-cm'1 region, where the strongest RR bands are found; Cu-N (His) stretching modes are expected in the 230-310-cm" 1 range. Stellacyanin and tree lacease have been reconstituted with 63Cu and 65Cu, and with D20, to assess the Cu and imidazole motions in the RR modes. A 2-cm" 1 D20/H20 shift identifies the 273-cm" 1 stellacyanin RR band as a Cu-N (His) mode; the extent of the shift sug-gests that the C2, as well as N3 imidazole, proton was replaced by D. Much smaller D20/H20 shifts are seen for the strong stellacyanin or lacease bands. The two strong RR bands of stellacyanin, 347 and 385 cm" 1, show 1.8-and 1.5-cm" 1 63Cu/65Cu isotope shifts; the combined shift is that calculated for the Cu-S (Cys) stretch. It is suggested that the pair of bands arises from strong coupling between the Cu-S stretching and SCC bending coordinates of the bound cysteine. The average frequency is~ 30 cm" 1 lower than the average fre-quencies of the strong bands in lacease, azurin, and plasto-cyanin, consistent with the longer extended X-ray absorption fine structure derived Cu-S distance in stellacyanin (2.19 Á) than in plastocyanin or azurin (2.13 Á). The lacease 63Cu/65Cu shifts, however, 0.5 cm'1 or less for the strong bands at 381, 405, and 420 cm'1, are much lower than those for stel-lacyanin and additional couplings are implicated. A variety of angle-bending modes of the coordinated ligands are expected in the 300-500-cm" 1 region, but it is difficult to account for resonance enhancement for most of them. It is suggested that torsional motions about the cysteine SC bond might con-tribute significantly to the resonance-enhanced modes. e “blue” or type 1 site of copper proteins has longattracted a great deal of interest, because of its unusual spectroscopic properties (Malkin & Malmstrom, 1970; Fee, 1975; Gray & Solomon, 1981). In the past few years, the molecular and electronic structure of this sitehas come sharply into focus thanks to the application of a battery of physical methods, including absorption and circular dichroism (CD) spectroscopy (McMillen et al., 1974a, b; Solomon et al., 1976a, b), nuclear magnetic resonance(NMR) spectroscopy (Markley et al., 1975; Hill et al., 1976; Ugerbil et al., 1977), electron paramagnetic resonance(EPR) spectroscopy (Vanngard, 1972),
影响因子：
3.4
作者：
Peisach,J;Powers,L;Blumberg,WE;Chance,B
通讯作者：
Chance,B