An aminopeptidase from Agave americana thermodynamic studies

Purified Agave aminopeptidase was characterized with respect to the thermodynamic properties of the reaction catalysed by the enzyme. Kinetic studies were conducted at different temperatures ranging from 7.8 to 45°. The energy of activation, E_a, as well as the constants ΔH, ΔF and ΔS were calculated for both the formation of the enzyme-substrate complex, and the dissociation of the enzyme-product complex. Kinetic studies in buffers with varying dielectric constants enabled the determination of the electrostatic as well as the non-electrostatic components of ΔS. These results fit well into the overall kinetic picture of this enzyme-catalysed reaction as reported previously.