Avaliação da Presença de Genes de Resistência e Virulência em Serratia marcescens e Identificação da Heterorresistência à Amicacina em Cepas de Serratia marcescens Resistentes aos Carbapenêmicos

• Grant number: 23/14763-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2024
• End date: April 30, 2026
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Maria Cristina da Silva Pranchevicius
• Grantee: Natália Ribeiro Crispim
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The growing incidence of antibiotic resistant bacteria is one of the major challenges in public health worldwide. Additionally, a phenomenon called heteroresistance, where resistant subpopulations of bacteria are present within a larger population of bacteria fully susceptible to antimicrobials, may be leading to the failure of antimicrobial-based treatments. Serratia marcescens is a pathogen responsible for various infections such as urinary tract infections, surgical wounds, and sepsis, especially in neonatal units and ICUs. S. marcescens is characterized by high levels of antibiotic resistance, a consequence of combined activity of intrinsic, acquired, and adaptive resistance elements. This study aims to investigate the resistance profile to some antibiotics in S. marcescens strains isolated from clinical samples, through phenotyping. The isolates will also be analyzed for the presence of resistance and virulence genes through PCR. Furthermore, we intend to identify subpopulations of S. marcescens heteroresistant to amikacin, the growth of biofilm among initial clinical isolates and heteroresistant subpopulations, and the potential mechanism of amikacin heteroresistance through the analysis of expression levels of some resistance genes and porins using quantitative reverse transcription PCR (RT-qPCR). Therefore, our results will provide significant insights into antibiotic resistance and amikacin heteroresistance in S. marcescens.