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：1982
卷号：79
期号：10
页码：3387-3389
DOI：10.1073/pnas.79.10.3387
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Thin-layer spectroelectrochemical methods have been employed to measure the reduction potentials of the blue copper in Polyporus versicolor laccase (EC 1.10.3.2 ) between 7{degrees}C and 41{degrees}C (0.2 M sodium phosphate, pH 5.4). Thermodynamic parameters are: {Delta}S{degrees} = -13.9 {+/-} 2 cal/mol-K; {Delta}H{degrees} = -22.1 {+/-} 0.5 kcal/mol; E{degrees} (25{degrees}C) = 780 {+/-} 3 mV vs. the normal hydrogen electrode. Comparison of the {Delta}S{degrees} and {Delta}H{degrees} values with those for single-site proteins suggests that the high potential of the blue copper in fungal laccase is attributable mainly to stabilization of the copper (I) center by enhanced ligand binding interactions and that protein solvation effects play a lesser role.
