Caracterização genômica de serratia marcescens em animais da região do Vale do Catimbau

Abstract

Antimicrobial resistance represents one of the greatest global challenges to public health, driven mainly by the spread of resistance genes between different environments and hosts. This study sought to carry out the genomic characterization of 14 strains of Serratia marcescens isolated from animals in the Vale do Catimbau National Park in Pernambuco, Brazil. The strains were isolated using rectal and ear swabs, followed by biochemical tests and antibiograms, which confirmed the multidrug resistance of the isolates by resisting more than four different classes. These isolates were then subjected to sequencing and, subsequently, genomic assembly and analysis of the isolates was carried out, with the aim of mapping resistance and virulence genes, as well as identifying mobile genetic elements (MGEs) that may contribute to genomic plasticity and environmental adaptation. The average nucleotide identity analysis revealed that all the isolates belong to the S. marcescens complex, with high genomic similarity between the species in the complex (ANI > 95%). In addition, the phylogenomic analysis using orthologous genes as a metric showed paraphyletic clades between strains of different species. We identified 72 virulence genes and 35 resistance genes dispersed among the 14 strains. In addition, genomic islands containing resistance genes were mapped, indicating a possible horizontal transfer of genes. The antibiogram results partially corroborated the genomic profiles, suggesting that the resistance observed in some isolates may be related to horizontally acquired genes. These results show the standard genomic profile of resistance in the complex, as well as mapping the genes present by geographical region. This study reinforces the importance of monitoring resistance genes in natural environments, which can be called “reservoirs of resistance genes”, highlighting the need for an integrated “One Health” approach to mitigate the spread of multidrug-resistant strains. The detection of resistance genes in S. marcescens from wild animals presents the potential for interaction between rural and urban environments, contributing to the emergence of new threats to human and animal health.