IAL   21557
INSTITUTO DE AGROBIOTECNOLOGIA DEL LITORAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Functional characterization of methionine sulfoxide reductase A from Trypanosoma spp.
Autor/es:
ARIAS DIEGO G.; IGLESIAS ALBERTO A.; GUERRERO SERGIO A.
Lugar:
Casa Pueblo, Punta Ballena, Maldonado
Reunión:
Simposio; Thiol metabolism and redox regulation of cellular functions; 2011
Institución organizadora:
UDELAR-IP Montevideo
Resumen:
Methionine is an amino acid susceptible to being oxidized to methionine sulfoxide (MetSO). The reduction ofMetSO to methionine is catalyzed by methionine sulfoxide reductase (MSR), an enzyme present in almost allorganisms. In trypanosomatids, the study of antioxidant systems has been mainly focused on the involvementof trypanothione, a specific redox component in these organisms. However, no information is availableconcerning their mechanisms for repairing oxidized proteins, which would be relevant for the survival ofthese pathogens in the various stages of their life cycle. We report the molecular cloning of three genesencoding a putative A-type MSR in trypanosomatids. The genes were expressed in Escherichia coli, and thecorresponding recombinant proteins were purified and functionally characterized. The enzymes were specificfor L-Met(S)SO reduction, using Trypanosoma cruzi tryparedoxin I as the reducing substrate. Each enzymemigrated in electrophoresis with a particular profile reflecting the differences they exhibit in superficialcharge. The in vivo presence of the enzymes was evidenced by immunological detection in replicative stagesof T. cruzi and Trypanosoma brucei. The results support the occurrence of a metabolic pathway in Trypanosomaspp. involved in the critical function of repairing oxidized macromolecules.