IDENTIFICATION AND EXPRESSION OF GENES THAT AFFECT THE PHENOTYPIC ANTIMICROBIAL RESISTANCE AFTER CONJUGATIVE PLASMIDS ACQUISITION BY ENTEROBACTERIACEAE

• Grant number: 25/09728-4
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: October 01, 2025
• End date: September 30, 2026
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Angelo Berchieri Junior
• Grantee: Viviane Amorim Ferreira
• Supervisor: Rafael Felipe da Costa Vieira
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Institution abroad: University of North Carolina at Charlotte (UNCC), United States
• Associated to the scholarship: 24/10213-6 - FACTORS ASSOCIATED WITH THE EXPRESSION OF ANTIMICROBIAL RESISTANCE GENES ACQUIRED THROUGH CONJUGATIVE PLASMIDS IN Enterobacteriaceae, BP.DR

Abstract

Antimicrobial resistance is one of the greatest threats to One Health, due to failures in infection treatments and the difficulty of discovering new effective molecules. In the poultry production environment, antimicrobial residues are frequently found, which can interfere with genetic and epigenetic mechanisms of various microorganisms with zoonotic potential, including Escherichia coli and Salmonella enterica. The Salmonella serovars Typhimurium, Enteritidis, and Heidelberg showed increased resistance after acquiring the IncB/O pH2332-107 plasmid through conjugation under subinhibitory concentrations of antimicrobials. This was confirmed through MIC testing, which revealed values up to 16 times higher in Salmonella spp. than in Escherichia coli after acquiring the plasmid. Therefore, this study aims to elucidate the reason behind this significant increase in resistance in Salmonella spp. compared to Escherichia coli through whole-genome sequencing and analysis, to identify resistance genes and those related to the secondary resistome, in addition to comparative sequence analysis, and ddPCR plus RT-qPCR to assess gene expression in both bacterial genera. (AU)