First Genome-Based Characterisation and Staphylococcal Enterotoxin Production Ability of Methicillin-Susceptible and Methicillin-Resistant Staphylococcus aureus Strains Isolated from Ready-to-Eat Foods in Algiers (Algeria)

is a pathogenic microorganism of humans and animals, able to cause foodborne intoxication due to the production of staphylococcal enterotoxins (SEs) and to resist antibiotic treatment as in the case of methicillin-resistant (MRSA). In this study, we performed a genomic characterisation of 12 genetically diverse strains isolated from ready-to-eat foods in Algiers (Algeria). Moreover, their ability to produce some classical and new staphylococcal enterotoxins (SEs) was investigated. The 12 strains resulted to belong to nine known sequence types (STs) and to the novel ST7199 and ST7200. Furthermore, SA46 was assigned to the European clone MRSA-ST80-SCC -IV. The 12 strains showed a wide endowment of and (staphylococcal enterotoxin-like toxin) genes ( , , , , , , , , , , , , , 2, , , , 30; 1- 2), including variants and pseudogenes, and harboured the enterotoxin gene cluster ( ) types 1 and 5. Additionally, they produced various amounts of (64.54-345.02 ng/mL), SEB (2871.28-14739.17 ng/mL), SED (322.70-398.94 ng/mL), SEH (not detectable-239.48 ng/mL), and SER (36,720.10-63,176.06 ng/mL) depending on their genotypes. The genetic determinants related to their phenotypic resistance to β-lactams ( Z, A), ofloxacin ( A-S84L), erythromycin ( B), lincomycin ( S), kanamycin ( (3')-III, (6)-I), and tetracyclin ( (L), (38)) were also detected. A plethora of virulence-related genes, including major virulence genes such as the gene, determinant for the toxic shock syndrome toxin-1, and the F-PV and S-PV genes, encoding the panton-valentine leukocidin (PVL), were present in the strains, highlighting their pathogenic potential. Furthermore, a phylogenomic reconstruction including worldwide foodborne showed a clear clustering based on ST and geographical origin rather than the source of isolation.