Structural basis of sensibility of Mycobacterium tuberculosis and M. leprae dihydropteroate synthase to the sulfonamide drugs

• Grant number: 14/24486-2
• Support type: Scholarships in Brazil - Master
• Effective date (Start): July 01, 2015
• Effective date (End): June 30, 2017
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal researcher: Marcio Vinicius Bertacine Dias
• Grantee: João Henrique Pimenta Giudice
• Home Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 10/15971-3 - Structural characterization of enzymes from antibiotic biosynthetic pathways with biotechnological interest, AP.JP

Abstract

Two diseases which have mycobacterium as etiologic agents and are a serious problem of public health as in Brazil as in other in development countries, are tuberculosis and leprosy. Tuberculosis, which is caused by Mycobacterium tuberculosis, is one of the main causes of death by infection diseases of the human population. While leprosy, which is caused by M. leprae, although is not lethal, is responsible to cause the invalidity of patients in an advanced stage of the infection and it is one the most ancient infection disease of human population. Despite the socioeconomic importance of these two diseases, the understanding of infectious agent biology and the development of new drugs are still necessary. The folate pathway biosynthesis is attractive for the development of new molecules because it is essential for the growth of both microorganisms. Actually, leprosy can be treated with dapsone, which is a sulfonamide drug and inhibits the enzyme dihydropteroate synthase (DHPS), the fourth step in this pathway. On the other hand, there is not any sulfonamide drug which has effect on M. tuberculosis, even with the very high sequential identity of those two enzymes. Although the DHPS structure is known, there is no information about the bound mechanism of its substrate p-ABA and there is no crystallographic structure for M. leprae DHPS. In this project, we aim to study the p-ABA bond mechanism and also the sulfonamide drugs to the DHPS from M. tuberculosis and M. leprae. We will use X-ray crystallography to solve the DHPS structures of these two organisms in complex with p-ABA and also dapsone. We also intend to use site direct mutagenesis, enzymatic assays and calorimetry to understand the specificity differences for these two enzymes to sulfas. We expect with these results unveil questions that may contribute to understand the mechanism of action of sulfas and also add information that might be useful to develop new drugs to tuberculosis. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RIBEIRO, JOAO AUGUSTO; CHAVEZ-PACHECO, SAIR MAXIMO; DE OLIVEIRA, GABRIEL STEPHANI; SILVA, CATHARINA DOS SANTOS; PIMENTA GIUDICE, JOAO HENRIQUE; LIBREROS-ZUNIGA, GERARDO ANDRES; BERTACINE DIAS, MARCIO VINICIUS. Crystal structures of the closed form of Mycobacterium tuberculosis dihydrofolate reductase in complex with dihydrofolate and antifolates. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY, v. 75, n. 7, p. 682-693, JUL 2019. Web of Science Citations: 0.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

. Structural and biophysical studies of three folate pathway enzymes of pathogenic microorganisms.. 2018. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) São Paulo.