Avaliação da expressão do antígeno 503 de Leishmania I. Chagasi por Escherichia coli M15 utilizando diferentes concentrações de IPTG

Abstract

Visceral leishmaniasis is an infectious-parasitic disease caused by protozoa of the genus Leishmania, which can be lethal when there is no adequate treatment. The increasing incidence of this disease makes important the search for alternatives of low cost for rapid diagnosis and vaccine. In this context, the main objective of this research was to evaluate the influence of IPTG on 503 antigen expression of Leishmania i. chagasi expressed in Escherichia coli. The bacteria was cultured in three different assays, called Kinetics A, B, C where the concentration of the IPTG inducer was varied at 10, 100 and 1500 μM respectively. It was observed that in Kinetics C (1500μM), it was obtained a higher concentration of native proteins and from a qualitative analysis (electrophoresis) it was observed that in Kinetics A and C obtained the best expression of 503 antigen. For purification of the antigen, the Nickel Sepharose Resin, operated in fixed bed was used. The qualitative results of the purification showed that it was not efficient