Rydén L
Department of Biochemistry, Uppsala University, Sweden.
Prog Clin Biol Res. 1988;274:349-66.
The evolutionary relationships of blue copper proteins are reviewed. Five homologous families of small blue proteins are recognized. Despite differences in length their peptide chains can all be accommodated into the eight-stranded fold of plastocyanin with some adjustments at three of the loops and the two termini. The C-termini of the blue oxidases ceruloplasmin and Neurospora laccase also fit into this fold and they are suggested to be homologous to the small blue proteins. The alignment of their amino acid sequences suggest some of the histidines to be binding active site copper. A superposition of the structures of poplar plastocyanin and bovine Cu-Zn superoxide dismutase (SOD) showed that 68 out of 99 alpha-carbons in plastocyanin overlapped with corresponding atoms in SOD with a rms distance of 2.99 A. In addition three of the histidine residues that were proposed to be copper-binding in laccase and ceruloplasmin aligned with ligands to the Cu-Zn pair in a SOD. Thus also SOD might be related to the blue proteins.
本文综述了蓝色铜蛋白的进化关系。现已识别出五个小蓝色蛋白的同源家族。尽管它们的肽链长度存在差异，但经过三个环和两个末端的一些调整后，它们都可以容纳到质体蓝素的八链折叠结构中。蓝色氧化酶铜蓝蛋白和粗糙脉孢菌漆酶的C末端也适合这种折叠结构，因此它们被认为与小蓝色蛋白同源。它们的氨基酸序列比对表明，一些组氨酸是结合活性位点铜的部位。杨树质体蓝素和牛铜锌超氧化物歧化酶（SOD）结构的叠加显示，质体蓝素99个α-碳原子中的68个与SOD中的相应原子重叠，均方根距离为2.99 Å。此外，漆酶和铜蓝蛋白中被认为与铜结合的三个组氨酸残基与SOD中铜锌对的配体对齐。因此，SOD可能也与蓝色蛋白有关。
