Wigfield D C, Goltz D M
Ottawa-Carleton Chemistry Institute, Department of Chemistry, Carleton University, Ont., Canada.
Biochem Cell Biol. 1993 Jan-Feb;71(1-2):96-8. doi: 10.1139/o93-015.
The reaction of apotyrosinase with divalent copper to give enzymatically active tyrosinase has been studied at pH 8.2 and temperatures from 278 to 303 K. At a 10-fold excess of Cu(II) over enzyme, the pseudo-first order rate constants range from 1.32 x 10(-3) s-1 to 2.93 x 10(-2) s-1 and yield activation parameters of delta H not equal to = 85 +/- 3 kJ.mol-1 and delta S not equal to = 5 +/- 20 J.mol-1.K-1. The near zero value for the entropy of activation is discussed.