Functional and structural studies about the sulfate ABC transporter in Xanthomonas citri

• Grant number: 13/16094-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2013
• End date: December 31, 2017
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Andrea Balan Fernandes
• Grantee: Cristiane Tambascia Pereira
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 15/26203-0 - Characterization of the sulfur ABC transport in Xanthomonas citri : A structural view, BE.EP.DR

Abstract

X. citri is a pathogen of great interest because it is responsible for the development of citrus canker in plants. Much effort has been performed to characterize the mechanisms that affect the growth, infection and pathogenesis, but little is known about the metabolism of this bacterium in relation to the uptake of ions, and in particular the metabolism of sulfur. In recent studies performed by our group (FAPESP 2010/14207-8) have identified and functionally characterized proteins belonging to the sulfate uptake and reduction to sulfide ions, which include an ABC-type transporter system consisting of the periplasmic binding protein Spb, two permeases (CysWU) and two ATPases (CysA), and the enzymes CysNCD, CysIJH and CysG. In a study conducted by our group it was demonstrated that this pathway is complete in X. citri and it is activated during growth in M9 minimal medium and rich medium LB. Additionally, activation of the operon encoding the ABC transporter was fully demonstrated in vitro and in vivo, indicating the importance of this transporter during growth and infection of bacteria in Citrus sinensis (orange pear). Thus, this work aims to further characterize the mechanism of transport of sulfate through structural and functional studies of the type ABC transporter, specifically, the periplasmic-binding protein Sbp, the membrane components and the ATPases. The target proteins will be expressed and purified for studies of interaction with sulfate, protein-protein interactions and structural analysis by crystallography. Additionally, the relevance of this transporter during the growth of bacteria and infection will be evaluated using mutants of X. citri with a deletion in the gene sbp (Xac1017). This will be a pioneering work on the characterization of the importance of sulfate ABC transporter to X. citri indicating possible targets for the development of inhibitors. Additionally, the structural components of this transporter, which involves two membrane proteins, will greatly impact on the scientific community and will be of great importance for studies of ion uptake in bacteria.

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)

PEREIRA, CRISTIANE TAMBASCIA; ROESLER, CASSIA; FARIA, JESSICA NASCIMENTO; FESSEL, MELISSA REGINA; BALAN, ANDREA. Sulfate-Binding Protein (Sbp) from Xanthomonas citri: Structure and Functional Insights. MOLECULAR PLANT-MICROBE INTERACTIONS, v. 30, n. 7, p. 578-588, JUL 2017. (13/09172-9, 13/16094-4)

Academic Publications

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

PEREIRA, Cristiane Tambascia. Functional and Structural analysis about sulfate ABC transporter in Xanthomonas citri. 2017. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia Campinas, SP.