Plasmodium falciparum lacks sialidase and trans-sialidase activity

• Published in: Parasitology Vol. 112 ( Pt 5); p. 443
• Main Authors: Clough, B, Atilola, F A, Healy, N, Pereira, M E, Bethell, R C, Penn, C R, Pasvol, G
• Format: Journal Article
• Language: English
• Published: England 01.05.1996
• Subjects: Animals; Cell Adhesion; Enzyme Inhibitors - pharmacology; Erythrocytes - parasitology; Guanidines; Humans; Neuraminidase - antagonists & inhibitors; Neuraminidase - metabolism; Orthomyxoviridae - enzymology; Plasmodium falciparum - enzymology; Plasmodium falciparum - growth & development; Plasmodium falciparum - pathogenicity; Pyrans; Rosette Formation; Sialic Acids - pharmacology; Zanamivir
• ISSN: 0031-1820; 1469-8161
• DOI: 10.1017/S0031182000076903

Sialic acid on the red cell surface plays a major role in invasion by the malaria parasite Plasmodium falciparum. The NeuAc(alpha 2,3) Gal motif on the O-linked tetrasaccharides of the red cell glycophorins is a recognition site for the parasite erythrocyte-binding antigen (EBA-175). Consequently, the interaction of P. falciparum and the red cell might share homology with that of the influenza virus. The cellular interactions of P. falciparum were examined for their sensitivity to 4-guanidino-2,3-didehydro-D-N-acetyl neuraminic acid (4-guanidino Neu5Ac2en), a potent inhibitor of influenza virus sialidase. Parasite invasion and subsequent development was unaffected by the sialidase inhibitor. The inhibitor did not affect rosette formation of parasite-infected erythrocytes with uninfected cells nor their cytoadherence to C32 melanoma cells. Furthermore, we were unable to confirm the presence of a previously reported parasite sialidase using sensitive fluorometric or haemagglutination assays, neither was any malarial trans-sialidase identified. We conclude that P. falciparum possesses neither sialidase nor trans-sialidase activity and that an inhibitor of influenza virus sialidase has no effect on important cellular interactions of this parasite.