Holwerda R A, Knaff D B, Gray G O, Harsh C E
Biochemistry. 1981 Jul 21;20(15):4336-40. doi: 10.1021/bi00518a016.
The reactivity of cuprous stellacyanin as a quinone and semiquinone reductase has been examined. Rate constants (25.0 degrees C) measured for the oxidation of stellacyanin by 1,4-benzoquinone and benzosemiquinone are 2.3 X 10(4) M-1 s-1 (delta H not equal to = 4.4 kcal/mol, delta S not equal to = -24 eu) and 5.1 X 10(6) M-1 s-1, respectively [pH 7.0, I = 0.1 M (phosphate)]. The agreement of these rate constants with those calculated on the basis of relative Marcus theory is discussed. Stellacyanin is more effective than laccase in quenching benzosemiquinone, suggesting that the physiological role of this metalloprotein is to regulate the concentration of free radicals generated through the laccase-catalyzed oxidation of phenols.
已对铜蓝蛋白作为醌和半醌还原酶的反应活性进行了研究。在25.0℃下测得的铜蓝蛋白被1,4 - 苯醌和苯半醌氧化的速率常数分别为2.3×10⁴ M⁻¹ s⁻¹（ΔH≠ = 4.4 kcal/mol，ΔS≠ = -24 eu）和5.1×10⁶ M⁻¹ s⁻¹ [pH 7.0，I = 0.1 M（磷酸盐）]。讨论了这些速率常数与基于相对马库斯理论计算得出的速率常数的一致性。铜蓝蛋白在淬灭苯半醌方面比漆酶更有效，这表明这种金属蛋白的生理作用是调节通过漆酶催化酚类氧化产生的自由基浓度。
