M. Duque et al., NEW FLUOROGENIC TRIACYLGLYCEROL ANALOGS AS SUBSTRATES FOR THE DETERMINATION AND CHIRAL DISCRIMINATION OF LIPASE ACTIVITIES, Journal of lipid research, 37(4), 1996, pp. 868-876
A new type of fluorogenic and isomerically pure 1(3)-O-alkyl-2,3 (3,2)
-diacyl glycerols was synthesized that can be used as substrate for th
e determination of lipase activities. These compounds contain a fluore
scent pyrene acyl chain and, as a potent quencher of pyrene fluorescen
ce, a trinitrophenylamino acyl residue. In their intact form, the fluo
rogens show only low fluorescence intensity. Upon lipase-induced or ch
emical hydrolysis of the substrates, however, the fluorophore and quen
cher separate from each other. This leads to a gradual increase in pyr
ene fluorescence, reflecting the time-dependent progress of lipolysis
and, under substrate saturation conditions, lipase activity. This lipa
se assay is continuous and does not require separation of substrate an
d reaction products. Short- and long-chain homologues as well as optic
al isomers of the fluorogenic alkyldiacyl glycerols were hydrolyzed by
pancreatic lipase, hepatic lipase, and lipoprotein lipase at highly d
ifferent rates depending on the substrate or enzyme preparation and so
urce (e.g., postheparin plasma or cultured cells). It is proposed that
a useful set of enantiomeric and/or homologous substrates in combinat
ion with appropriate reaction media might be applied to the selective
determination of a lipase in a mixture of lipases, e.g., hepatic and l
ipoprotein lipase in PHP, for medical diagnostics.-Duque, M., M. Graup
ner, H. Stutz, I. Wicher, R. Zechner, F. Paltauf, and A. Hermetter. Ne
w fluorogenic triacylglycerol analogs as substrates for the determinat
ion and chiral discrimination of lipase activities.