J. Biol. Chem., Vol. 259, Issue 13, 8163-8167, 07, 1984
The malarial pigment in rat infected erythrocytes and its interaction with chloroquine. A Mossbauer effect study
A Yayon, ER Bauminger, S Ofer and H Ginsburg
Mossbauer studies of rat erythrocytes infected by Plasmodium berghei
malaria parasites, using 57Fe-enriched rat red blood cells, were carried
out in order to determine the physical parameters which characterize the
malarial pigment iron and to test the effect of the widely used antimalaria
drug, chloroquine, on these parameters. The iron in the malarial pigment
which is derived from hemoglobin digestion by the intracellular parasite
was found to be trivalent, high spin, with Mossbauer parameters which are
significantly different from those of any known iron porphyrin containing
compound. No difference was found between the parameters obtained in
erythrocytes infected by drug- sensitive and drug-resistant strains of P.
berghei, both before and after the treatment with chloroquine. The iron
compound consists of microaggregates, about 30 A in diameter. These are
somewhat larger in chloroquine-resistant strains and tend to increase in
size in chloroquine-sensitive strains upon treatment with the drug.
Mossbauer spectra of erythrocytes infected by a chloroquine-resistant
strain revealed pigment iron in relative amounts invariable of those found
in chloroquine-sensitive strains, demonstrating that drug-resistant
parasites indeed digest hemoglobin.