VWA7 – A Putative Human Phosphatidylcholine-specific Phospholipase C

For over four decades, the existence of mammalian phosphatidylcholine-specific phospholipase C (pc-PLC) has been reported. However, the gene encoding this enzyme has not been unambiguously determined to date. This study presents human von Willebrand factor A domain-containing protein 7 (VWA7) as putative pc-PLC and provides some biochemical insights into its potential function. Structural comparison of the modelled N-terminal region of VWA7 with Bacillus cereus pc-PLC revealed high similarity and, remarkably, a conserved active site architecture. The localization and activity of different VWA7 versions were investigated in mammalian cells. Eventually, pc-PLC activity was confirmed for VWA7 variants produced in bacteria, with the most active variant reaching 733 mU/mg. These findings establish a basis for future investigations on the role of human pc-PLC as well as on the poorly studied human VWA7.