Lipase-lipase interactions as a new tool to immobilize and modulate the lipase properties

Lipase from Burkholderia cepacia (formerly Pseudomonas fluorescens) (BCL) was previously immobilized on glyoxyl-agarose and the active site was blocked after incubation with diethyl-p-nitrophenylphosphate, obtaining a new "glyoxyl-BCL+" matrix to adsorbe lipases. Then. the soluble lipase was offered to this matrix at very low ionic strength. Under these conditions, the lipase was selectively adsorbed on this new matrix. This lipase-lipase interaction could be neglected with the use of Triton X-100 as detergent. In addition, the close contact between the adsorbed lipase and the immobilized lipase permitted to alter the catalytic and functional properties of this lipase. For example. the enantioselectivity of the BCL adsorbed on glyoxyl-BCL+ varied its E value from 10 at pH 7 and 25 degreesC up to >100 at pH 5 and 25 degreesC in the hydrolytic resolution of (+/-)-2-hydroxy-4-phenylbutyric acid ethyl ester. These results can open new routes for the modulation of lipase properties. (C) 2004 Elsevier Inc. All rights reserved.