Biochemical characterization of Plasmodium falciparum hemozoin.

Hemozoin, the pigment granule which develops within the blood stage food vacuole of the malaria parasite Plasmodium falciparum, was biochemically characterized. Hemozoin was found to be composed of 65% protein, 16% ferriprotoporphyrin-IX (hematin), 6% carbohydrate, and trace amounts of lipid and nucleic acids. The overwhelming majority of the protein component is a mixture of native and denatured human globin non-covalently associated with the metalloporphyrin. Immunoelectron microscopy, employing anti-human hemoglobin as a probe, identified in situ association of hemoglobin with hemozoin. Hemozoin produced within diabetic blood had a higher proportion of carbohydrate, suggesting that the carbohydrate component comes from non-enzymatic glycosylation of hemoglobin.