Molecular and Phenotypic Characterization of Salmonella Mbandaka Strains Isolated from Various Sources in Brazil

• Grant number: 25/10016-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2026
• End date: January 31, 2027
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Juliana Pfrimer Falcão
• Grantee: Thiago José da Cruz Neves
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Salmonella is one of the main agents responsible for foodborne illnesses in humans and also infects and causes disease in animals across several countries, including those in the European Union, the United States, and Brazil. The genus comprises two species: Salmonella bongori and Salmonella enterica. Infections caused by S. enterica can present in two forms: typhoid fever and salmonellosis. The latter is typically associated with a wide range of non-typhoidal serovars, such as S. Enteritidis, S. Typhimurium, S. Infantis, S. Mbandaka, among others. S. Mbandaka has been recognized as a relevant serovar associated with salmonellosis outbreaks and is notable for its high adaptability to multiple hosts and its ability to contaminate a wide variety of food sources. In recent years, the occurrence of Salmonella Mbandaka has increased in Brazil. Despite its clinical significance, relatively few studies have characterized strains of this serovar in the country. In this context, the aim of this study is to perform a molecular and phenotypic characterization of S. Mbandaka strains regarding their pathogenic potential, genetic diversity, and antimicrobial resistance. A total of 59 strains isolated from various sources in Brazil between 2010 and 2025 will be analyzed. The investigation will include the detection of virulence genes by PCR, the determination of antimicrobial resistance profiles using the disk diffusion method, and the genotypic characterization through PFGE, ERIC-PCR, and MLST. Additionally, phenotypic tests will be conducted to assess tolerance to acid and oxidative stress, as well as virulence assays using Galleria mellonella larvae. (AU)