Functional and structural studies of ABC transporters from Mycobacterium tuberculosis and Xanthomonas citri

• Grant number: 15/14514-1
• Support type: Regular Research Grants
• Duration: May 01, 2016 - October 31, 2018
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal researcher: Andrea Balan Fernandes
• Grantee: Andrea Balan Fernandes
• Home Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Membrane proteins are considered the new challenges of Structural Biology given their medical relevance. More than 50% of the targets of the pharmaceutical industry involve these proteins that represent about 30% of genomes of organisms. With the aim to set up a platform for expression and production of membrane proteins in our laboratory for use in functional and structural studies, we have chosen as targets ABC transporters (ATP_Binding cassette transporters), one of the largest families integral membrane proteins. ABC transporters have great medical and pharmaceutical relevance as they are related to the development of multiple drug resistance (MDR) in bacteria and cancer treatment, infectivity and pathogenesis. Although extensively studied in many organisms, there are few functional or structural studies on these transporters in Mycobacterium tuberculosis or Xanthomonas citri, two pathogenic bacteria studied by our group.In recent works, we have shown the importance of ABC family components for the infection and pathogenicity of X. citri, including the presence of at least four transporters related to the uptake of sulfate (SbpCysUWA) and sulfonated compounds (SsuABCDE). The resolution of the structure of the binding protein Sbp in the presence of sulfate and biophysical assays confirmed their function and expression during in vivo assays. In parallel, in collaboration with Dr. Isabel de Moraes Diamond Membrane Protein Laboratory Light Source and OPPF (Oxford Protein Production Facility) in Oxfordshire, we have cloned and carry out analysis of expression of 17 ABC transporters from M. tuberculosis, most involved in drug efflux as well as in the assimilation of essential molecules for cellular metabolism. Given the importance of these transporters, the absence of functional data and the experience of our group in this family of proteins, this project is intended to perform functional and structural characterization of the M. tuberculosis ABC transporters for glutamine (genes Rv2563/Rv2564), drug efflux (gene Rv1747) and the sulfate transporter of X. citri (SbpCysUWA). In this sense, it is intended to express, purify and to produce the transporter components in the complex or individually for the resolution of their crystal structures followed by functional studies. Additionally, the development of this project will be of great importance for the formation of a group with experience in handling of membrane protein for functional and structural studies, an area still poorly developed in Brazil. (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)

GUERRA, GABRIEL SOARES; BALAN, ANDREA. Genetic and structural determinants on iron assimilation pathways in the plant pathogen Xanthomonas citri subsp. citri and Xanthomonas sp.. Brazilian Journal of Microbiology, v. 51, n. 3, DEC 2019. (15/14514-1)

MEZA, A. N.; CAMBUI, C. C. N.; MORENO, A. C. R.; FESSEL, M. R.; BALAN, A.. Mycobacterium tuberculosis CysA2 is a dual sulfurtransferase with activity against thiosulfate and 3-mercaptopyruvate and interacts with mammalian cells. SCIENTIFIC REPORTS, v. 9, NOV 14 2019. (14/20921-6, 15/14514-1, 16/03196-1, 18/20162-9)