Functional Reconstitution of the Plasmodium GPI:protein transamidase Complex

GPI Saj.pdf168.3 KB

Proteins that have a GPI glycolipid modification are acknowledged to be key in the lifecycle of Plasmodium; for example the involvement of the GPI-anchored MSP1 on merozoites in erythrocyte invasion.  The enzyme that transfers the preformed GPI to the proteins such as MSP1 is named GPI:protein transamidase, however, studying this enzyme biochemically has been arduous, due to the following hurdles. Firstly, the GPI:protein transamidase functions as a subunit in multidomain complex, some components of which maybe membrane associated, and there are no reports of functional recombinant reconstitution of this complex.  Secondly, there are no convenient and sensitive transamidase assays available that are amenable to medium/high throughput studies, even though large small molecule cysteine peptidase inhibitor libraries exist and can be used to studying this enzyme.

Any input/thoughts on how to overcome the aforementioned obstacles in studying the Plasmodium GPI:protein transamidase would be most welcome. Please peruse the attached file.