Determination of the quantitative stereoselectivity fingerprint of lipases during hydrolysis of a prochiral triacylglycerol

We propose a method for characterizing quantitatively the stereoselectivity of lipases during hydrolysis of triacylglycerols. Although it is of general applicability, we demonstrate it specifically for sn-1,3-regiospecific lipases. In this case the method generates a “stereoselectivity fingerprint” that consists of ratios of the specificity constants for the various reactions that produce and consume the 1,2-sn- and 2,3-sn-diacylglycerols. We use the method to determine the stereoselectivity fingerprint of several lipases during the hydrolysis of the prochiral substrate triolein. Our method opens up the possibility of correlating quantitative fingerprints with structural information, in the quest to elucidate the mechanisms underlying the stereoselectivity of lipases.