Spectroscopic and calorimetric assays reveal dependence on dCTP and two metals (Zn2+ + Mg2+) for enzymatic activity of Schistosoma mansoni deoxycytidylate (dCMP) deaminase

Autor(es)

Scortecci, Jessica Fernandes ; Balasco Serrao, Vitor Hugo ; Cheleski, Juliana ; Torini, Juliana Roberta ; Romanello, Larissa ; DeMarco, Ricardo ; Pereira, Humberto D'Muniz

• Tipo de documento: Artigo Científico
• Fonte: BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS; v. 1865, n. 11, p. 10-pg., 2017-11-01.

Resumo

The parasite Schistosoma mansoni possess all pathways for pyrimidine biosynthesis, whereby deaminases play an essential role in the thymidylate cycle, a crucial step to controlling the ratio between cytidine and uridine nucleotides. In this study, we heterologously expressed and purified the deoxycytidylate (dCMP) deaminase from S. mansoni to obtain structural, biochemical and kinetic information. Small-angle X-ray scattering of this enzyme showed that it is organized as a hexamer in solution. Isothermal titration calorimetry was used to determine the kinetic constants for dCMP-dUMP conversion and the role of dCTP and dTTP in enzymatic regulation. We evaluated the metals involved in activating the enzyme and show for the first time the dependence of correct folding on the interaction of two metals. This study provides information that may be useful for understanding the regulatory mechanisms involved in the metabolic pathways of S. mansoni. Thus, improving our understanding of the function of these essential pathways for parasite metabolism and showing for the first time the hitherto unknown deaminase function in this parasite. (AU)

• Processo FAPESP: 12/05532-8 - Estudos estruturais e cinéticos das enzimas Adenosina Kinase, Hipoxantina-guanina Fosforibosiltransferase, Adenilsuccinato Sintetase e Adenilsuccinato Liase de Schistosoma mansoni
• Beneficiário: Larissa Romanello
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 12/14223-9 - Estudos estruturais e cinéticos das enzimas da via de salvação de purina de Schistosoma mansoni
• Beneficiário: Humberto D'Muniz Pereira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/15777-8 - Estudos estruturais e cinéticos da enzima Desoxicitidilato desaminase (DEOC) de Schistosoma mansoni
• Beneficiário: Jessica Fernandes Scortecci
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 12/23730-1 - Caracterização das interações macromoleculares das proteínas envolvidas na síntese de selenocisteínas em escherichia coli
• Beneficiário: Vitor Hugo Balasco Serrão
• Modalidade de apoio: Bolsas no Brasil - Doutorado