In-solution behavior and protective potential of asparagine synthetase A from Trypanosoma cruzi

Publication date: Available online 15 March 2019Source: Molecular and Biochemical ParasitologyAuthor(s): Flávia Souza Morini, Emanuella de Castro, Stephanie Bath de Morais, Cesar Lancheros Contreras, Ana Valéria Pereira Weiler, Mario Tyago Murakami, Phileno Pinge-Filho, Sueli Fumie Yamada-Ogatta, Tatiana de Arruda Campos Brasil de SouzaAbstractL-Asparagine synthetase (AS) acts in asparagine formation and can be classified into two families: AS-A or AS-B. AS-A is mainly found in prokaryotes and can synthetize asparagine from ammonia. Distinct from other eukaryotes, Trypanosoma cruzi produces an AS-A. AS-A from Trypanosoma cruzi (Tc-AS-A) differs from prokaryotic AS-A due to its ability to catalyze asparagine synthesis using both glutamine and ammonia as nitrogen sources. Regarding these peculiarities, this work uses several biophysical techniques to provide data concerning the Tc-AS-A in-solution behavior. Tc-AS-A was produced as a recombinant and purified by three chromatography steps. Circular dichroism, dynamic light scattering, and analytical size exclusion chromatography showed that Tc-AS-A has the same fold and quaternary arrangement of prokaryotic AS-A. Despite the tendency of protein to aggregate, stable dimers were obtained when solubilization occurred at pH ≤ 7.0. We also demonstrate the protective efficacy against T. cruzi infection in mice immunized with Tc-AS-A. Our results indicate that immunization with Tc-AS-A might confer partial protection to infectiv...

Source: Molecular and Biochemical Parasitology - March 17, 2019 Category: Parasitology Source Type: research