Abstract for the URSS Portfolio – Sophie Martucci
Calcium independent phospholipase A2β (iPLA2β) is putatively involved with vascular
inflammation,[1] hence identifying antagonists of the enzyme could lead to potential new
therapeutic drugs in the fields of cardiovascular medicine. In order to establish an in vitro screen for
inhibitors, the archetypal enzyme model patatin isolated from potato tubers was studied.
Assays were conducted to test the enzyme activity in the presence and absence of BEL enantiomers.
Analysis showed that the assay followed classic Lineweaver-Burk kinetics. Optimal conditions for the
antagonist screen were determined to be 2 mM 4-nitrophenyl butyrate at 25 oC using 20-25 μg
enzyme per assay. R- and S-BEL were separately tested for antagonism both giving IC50 values in the
μM range. Binding has been simulated using Autodock Vina and 1oxw.pdb followed by molecular
dynamics with AMBER 12, which demonstrated each enantiomer can dock in the known active site.
Patatin was found to provide a straightforward assay for iPLA2β-like activity. Combining this with in
silico studies of novel antagonists, the process has the potential to form the basis of a highthroughput screen for compounds of therapeutic value in cardiovascular medicine.
1. Lui S, Xie Z, Zhao Q et al. J Biol Chem. 287:24738, 2012
2. Pots. A M et al Eur. J. Biochem. 252:66, 1998