Characterization of FAN1 DNA repair pathway in Pseudomonas aeruginosa

• Grant number: 24/03230-1
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: August 01, 2024
• End date: May 31, 2029
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Rodrigo da Silva Galhardo
• Grantee: Henrique Kustor Antonini
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 21/10577-0 - Biology of Bacteria and Bacteriophages Research Center, AP.CEPID

Abstract

Pseudomonas aeruginosa is a pathogenic bacterium considered a critical priority by the WHO for research and development of new antibiotics. Previous studies identified the FAN1 protein in this important microorganism, a homologue of the human DNA repair enzyme, and characterized its in vitro activity in the repair of interstrand crosslink lesions, however, the in vivo importance and other aspects of its function in the bacterial context have not been studied. The literature demonstrates that human FAN1 acts in at least two independent pathways, Fanconi anemia and mismatch repair, and that mutations in its gene are related to karyomegalic interstitial nephritis, Huntington's disease and predisposition to cancer, however, several aspects of its in vivo activity still need to be elucidated. P. aeruginosa has FAN1 encoded in an operon with PA1866, a protein of unknown function which shows homology with DNA helicases such as human FANCJ, which participates in the same pathways as FAN1, and also a domain similar to nucleases of the Cas4 family. Through this project we will characterize the DNA repair pathways involving FAN1 and PA1866 in P. aeruginosa. To this end, we intend to test their regulation as part of the SOS response, identify the genotoxic and mutagenic agents against which they provide protection, describe their genetic and protein interactions, study possible mutational signatures and also verify their participation in homologous recombination. With the results obtained, we hope not only to characterize in an unprecedented way the importance of these enzymes and their pathways in DNA repair in prokaryotes, but also to aid studies of their human counterparts.