期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1981
卷号：78
期号：11
页码：6567-6570
DOI：10.1073/pnas.78.11.6567
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The charge transfer spectra of plastocyanin and azurin are analyzed in detail, taking into account the structural information that is available. The number and relative energies of the low-lying charge transfer bands attributable to cysteine and methionine sulfur are considered with reference to the energy levels associated with the donor centers and to experimental work on relevant complexes. Two cysteine [->] Cu(II) charge transfer transitions are assigned to bands that occur near 620 nm and near 770 nm. Energy considerations suggest that the methionine [->] Cu(II) transition occurs in the vicinity of 550 nm for both plastocyanin and azurin. The existence of a disulfide linkage in stellacyanin is established by thiol titrations, and the possibility exists that the fourth ligand in stellacyanin may involve disulfide sulfur. If so, the cystine [->] Cu(II) transition is also expected to appear around 550 nm.
