Substrate efflux propensity plays a key role in the specificity of secretory A-type phospholipases.

ABSTRACT: To better understand the principles underlying the substrate specificity of A-type phospholipases (PLAs), a high throughput mass spectrometric assay was employed to study the effect of acyl chain length and unsaturation of phospholipids on their rate of hydrolysis by three different secretory PLAs in micelles and vesicle bilayers. With micelles, each enzyme responded differently to substrate acyl chain unsaturation and double bond position, probably reflecting differences in the accommodative properties of their substrate binding sites. Experiments with saturated acyl positional isomers indicated that the length of the sn2 chain was more critical than that of the sn1 chain, suggesting tighter association of the former with the enzyme. Only the first 9-10 carbons of the sn2 acyl chain seem

SUBMITTER: Haimi P 

PROVIDER: S-EPMC2804224 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature