Structural and biochemical characterization of Bacterial phosphatidylserine synthase

Abstract

Phospholipids account for a major portion of the cell membrane. Phosphatidylserine (PS) is one of the important phospholipids in mammals and bacteria. In bacteria, PS is produced by Phosphatidylserine synthase (PssA) in a single pathway. Although cellular localization and enzymology have been established for this protein, the structural basis for the reaction mechanism has not been elucidated in detail largely due to the lack of the high-resolution structure of lipid-bound PssA complex. To unveil the relationship between the function and the structure, purification, and crystallization of recombinant PssA from several bacterial species was attempted. In vitro activities of the recombinant E. coli PssA were successfully verified through LC-MS/MS analysis. Also, the formation of microcrystals of E. coli PssA complexed with 10PS diffracted to approximately 30 Å.