Metagenomic analysis and proteins prediction of emerging pathogens in artisanal cheese

Abstract

Currently, reports of the presence of emerging pathogens in cheeses are low and new outbreaks have occurred at an alarming rate, with the Vibrio and Aeromonas genera being the main causes of gastroenteritis in the world. Therefore, Multi-Omics integration has been a strategy to identify and develop detection methods for these pathogens in food. We investigated the presence of emerging pathogens in artisanal cheeses and predicted proteins with immunogenic potential, in silico, for food diagnostics. For this, multiomics integration was used: (a) metagenomics; (b) subtractive genomics; and (c) pan-genomics. Eight species of the genera Vibrio and Aeromonas were identified, the latter being the most abundant (89.7%) and identified in eight regions, with emphasis on the species A. caviae and A. veronii. Pan-genomic analyses revealed intra- and inter-species differences in both genera. Essential, non-cytoplasmic proteins were identified, without homology and with immunological potential for the species researched. Functional annotation of genes present in pan-genomic subsets reveals functionality between the core genome (transcription; amino acid transport and metabolism; and inorganic ion transport and metabolism) and the shared genome (signal transduction and carbohydrate transport and metabolism). A reinterpretation of the genomic plasticity of V. furnissii reveals the presence of mobile genetic elements critical for virulence in human isolates and the RTX toxin, also identified in this species, is present in the pathogenicity islands of V. alginolyticus and V. fluvialis. Collectively, the results provide important information for the development of a diagnostic strategy for emerging pathogens in food using immunoassays.

Keywords: Artisanal cheese; Emerging pathogens; Food quality; Immunoassay; Microorganisms; Multi-omics.