Three matrix metalloproteinases form a non-covalent association with the rhoptry-associated protein-1 of Plasmodium falciparum.
During the characterization of malaria vaccine candidate proteins, three metalloproteinases having a molecular mass of 220, 95 and 70 kDa were found to be co-isolated with the rhoptry-associated protein-1 (RAP-1) complex, but not with RAP-3 or gp195. These enzymes were also found in detergent extracts of saponin-lysed Plasmodium falciparum. Of nine proteinase inhibitors tested, only EDTA was found to abrogate activity. Dose-dependent curves were determined for several metal ions and cobalt was found to synergistically enhance enzyme activity. The gelatinases were immunoprecipitated with monospecific polyclonal antisera to macrophage and fibroblast gelatinase; however, these sera did not react with intracellular parasites by indirect immunofluorescence. These results indicate that the matrix metalloproteinases co-isolated with RAP-1 originate from human serum used to cultivate P. falciparum in vitro.
Locher
C P
CP
Department of Tropical Medicine and Medical Microbiology University of Hawaii at Manoa, John A. Burns School of Medicine, Honolulu 96816.
Vandekerckhove
F
F
Tam
L Q
LQ
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D003035:Cobalt / Q000494:pharmacology; D017364:Collagenases / Q000302:isolation & purification; D004789:Enzyme Activation / Q000187:drug effects; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D008666:Metalloendopeptidases / Q000302:isolation & purification / Q000378:metabolism*; D010963:Plasmodium falciparum / Q000378:metabolism*; D015800:Protozoan Proteins / Q000302:isolation & purification* / Q000378:metabolism*
D015800:Protozoan Proteins; C065352:rhoptry associated protein, Plasmodium; D003035:Cobalt; D017364:Collagenases; D008666:Metalloendopeptidases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D002118:Calcium