Generic placeholder image

Protein & Peptide Letters

Editor-in-Chief

ISSN (Print): 0929-8665
ISSN (Online): 1875-5305

Oxidation and Tyrosine Nitration Induce Structural Changes and Inhibits Plasmodium falciparum Falcipain-2 Activity In Vitro

Author(s): Jean B. Bertoldo and Hernán Terenzi

Volume 23, Issue 6, 2016

Page: [562 - 572] Pages: 11

DOI: 10.2174/0929866523666160411144635

Price: $65

Abstract

Falcipain-2 (FP2) is an important hemoglobinase from the malaria parasite Plasmodium falciparum and a suitable target for the development of an antimalarial chemotherapy. Many reports have indicated that radical nitrogen species (RNS) including nitric oxide (NO) are inhibitors of P. falciparum growth and promoters of recovery from malaria symptoms. In this scenario, FP2 emerges as a potential target of RNS, since its inhibition partially hinders the parasite growth. We report that in vitro FP2 did not undergo S-nitrosylation when exposed to the NO-donor GSNO. However, it was modified by a combined mechanism of methionine oxidation and tyrosine nitration in response to SIN-1, and NaNO2- H2O2 treatment. The treatments with the nitrating agents caused a pronounced decrease in protease activity most likely induced by a disruption on the secondary and tertiary structure of FP2. Our data also demonstrate that at least four tyrosine residues were nitrated and found on the surface of the enzyme, partially or completely exposed to the solvent. Although performed in vitro, these results suggest that falcipain-2 may be a target of RNS activity and its inhibition could explain the hindering of the parasite growth when exposed to these radicals. The understanding of the molecular mechanisms involving free radicals and its inhibition activity towards FP2 may be effective in the development of antimalarial therapies.

Keywords: Falcipain-2, FP2, nitration, Plasmodium falciparum, S-nitrosylation, 3-nitrotyrosine.

Graphical Abstract

Rights & Permissions Print Cite
© 2024 Bentham Science Publishers | Privacy Policy