title: Activation parameters for the reconstitution of apotyrosinase by copper.
abstract: 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.
authors.affiliation: Ottawa-Carleton Chemistry Institute, Department of Chemistry, Carleton University, Ont., Canada.
authors.forename: D C
authors.initials: DC
authors.lastname: Wigfield
authors.forename: D M
authors.initials: DM
authors.lastname: Goltz
mesh_terms: D001051:Apoenzymes / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D004789:Enzyme Activation; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D013816:Thermodynamics
chemical_list: D001051:Apoenzymes; D003300:Copper; D014442:Monophenol Monooxygenase