Antiparasitic effect of a fraction enriched in tight-binding protease inhibitors isolated from the Caribbean coral Plexaura homomalla

Emir Salas-Sarduy, Aymara Cabrera-Muñoz, Ana Cauerhff, Yamile González-González, Sebastián A. Trejo, Agustina Chidichimo, Maria de los Angeles Chávez-Planes, Juan José Cazzulo

Research output: Contribution to journalArticleResearchpeer-review

8 Citations (Scopus)


Malaria and American Trypanosomiasis constitute major global health problems. The continued emergence and spreading of resistant strains and the limited efficacy and/or safety of currently available therapeutic agents require a constant search for new sources of antiparasitic compounds. In the present study, a fraction enriched in tight-binding protease inhibitors was isolated from the Caribbean coral Plexaura homomalla (Esper, 1792), functionally characterized and tested for their antiparasitic activity against Trypanosoma cruzi and Plasmodium falciparum. The resultant fraction was chromatographically enriched in tight-binding inhibitors active against Papain-like cysteine peptidases (92%) and Pepsin-like aspartyl peptidases (8%). Globally, the inhibitors present in the enriched fraction showed no competition with substrates and apparent Ki values of 1.99 and 4.81nM for Falcipain 2 and Cruzipain, the major cysteine peptidases from P. falciparum and T. cruzi, respectively. The inhibitor-enriched fraction showed promising antiparasitic activity in cultures. It reduced the growth of the chloroquine-resistant P. falciparum strain Dd2 (IC50=0.46μM) and promoted the apparent accumulation of trophozoites, both consistent with a blockade in the hemoglobin degradation pathway. At sub-micromolar concentrations, the inhibitor-enriched fraction reduced the infection of VERO cells by T. cruzi (CL Brener clone) trypomastigotes and interfered with intracellular differentiation and/or replication of the parasites. This study provides new scientific evidence that confirms P. homomalla as an excellent source of tight-biding protease inhibitors for different proteases with biomedical relevance, and suggests that either the individual inhibitors or the enriched fraction itself could be valuable as antiparasitic compounds. © 2013 Elsevier Inc.
Original languageEnglish
Pages (from-to)611-622
JournalExperimental Parasitology
Issue number3
Publication statusPublished - 1 Nov 2013


  • Antiparasitic agents
  • Cysteine peptidases
  • Plasmodium falciparum
  • Plexaura homomalla
  • Tight-binding inhibitor
  • Trypanosoma cruzi


Dive into the research topics of 'Antiparasitic effect of a fraction enriched in tight-binding protease inhibitors isolated from the Caribbean coral Plexaura homomalla'. Together they form a unique fingerprint.

Cite this