Synopsis.
The malaria parasite Plasmodium falciparum , exports hundreds of
proteins into the red blood cells (RBC) it infects to help it grow and
replicate. Most exported proteins possess a five amino acid barcode that
acts as a proteolytic cleavage site and licenses these proteins for
export into the RBC compartment by protein translocating gateways
surrounding the parasite. We report here that the conserved fifth amino
acid position of the barcode plays an important role in the proteolytic
maturation of exported protein and, together with the downstream
flexible spacer region preceding the folded region of the exported
protein, are important for efficient transport into the RBC viaPlasmodium Translocon of Exported Proteins (PTEX).