Purification, Immobilization, Hyperactivation, and Stabilization of Lipases by Selective Adsorption on Hydrophobic Supports

Abstract

Immobilization of lipases on hydrophobic supports at low ionic strength permits one- step purification, immobilization, hyperactivation, and stabilization of most lipases. This selective adsorption occurs because the hydrophobic surface of the supports is able to promote the interfacial activation of the lipases, yielding enzyme preparations having the open form of the lipases very strongly adsorbed on these hydrophobic supports. At low ionic strength, only proteins having large hydrophobic pockets may become adsorbed on the hydrophobic support, and the only soluble proteins are lipases, which in closed form are fairly hydrophilic, but in open form expose a very hydrophobic pocket. The result- ing biocatalysts are therefore hyperactivated, at least with hydrophobic and small substrates (because all the enzyme molecules have the open form). Moreover, the stabilization of the open form of the lipases permits very highly stabilized enzyme preparations.