Structural characterization of type II secretion system (T2SS) effectors of Acinetobacter baumannii

• Grant number: 18/04344-0
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: April 01, 2018
• End date: September 30, 2022
• Field of knowledge: Biological Sciences - Biochemistry - Biochemistry of Microorganisms
• Principal Investigator: Andrea Dessen de Souza e Silva
• Grantee: Yuri Rafael de Oliveira Silva
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Associated research grant: 17/12436-9 - ANTIBIO-BAC: exploring the bacterial cell wall as a target for novel antibiotherapies, AP.SPEC
• Associated scholarship(s): 19/20836-2 - Structural study of the substrate delivery mechanism of the type II secretion system of Acinetobacter baumannii, BE.EP.DD

Abstract

Acinetobacter baumannii is a nosocomial pathogen accountable for millions of hospital-related infections per year in impaired patients. This pathogen has become more relevant in the last few years due to high rates of antibiotic resistance associated to it, leading it to the World Health Organization (WHO) priority list of bacteria for the development of new antibiotic treatments. Its infection and toxicity mechanisms are poorly understood in comparison to other pathogens, what makes it harder to develop new treatments against this microorganism. A. baumannii has a Type II Secretion System (T2SS) involved in pathogenicity, which exports the protease CpaA and the lipase LipA to the extracellular environment, however the roles of these effectors in infection are not stablished yet. These proteins depend on chaperones on the periplasm (CpaB and LipB, respectively) to be exported, another unexplained fact. The goal of this project is to characterize structurally the proteins CpaA and LipA in the presence and absence of their chaperones, CpaB and LipB, contributing to the elucidation of the transport mechanism in T2SS and of their roles in pathogenicity. We are going to clone, express and purify the enzymes and their chaperones so we can perform crystallization assays and x-ray diffraction to solve the tridimensional structures. The interaction between each pair of proteins are going to be studied using biophysical assays, and microbiological assays are going to be used to study their roles in virulence. These results will present the first informations in atomic-level detail about the effectors of T2SS in A. baumannii, and will open new doors for the development of new antibiotic treatments in the future. (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)

DE OLIVEIRA SILVA, YURI RAFAEL; CONTRERAS-MARTEL, CARLOS; MACHEBOEUF, PAULINE; DESSEN, ANDREA. Bacterial secretins: Mechanisms of assembly and membrane targeting. Protein Science, v. 29, n. 4, FEB 2020. (17/12436-9, 18/04344-0)

Academic Publications

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

SILVA, Yuri Rafael de Oliveira. Structural characterization of type II secretion system (T2SS) effectors of Acinetobacter baumannii. 2022. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia Campinas, SP.