Oxacillin-susceptible mecA-positive Staphylococcus aureus associated with processed food in Europe

• Published in: Food microbiology Vol. 82; pp. 107 - 110
• Main Authors: Quijada, Narciso M., Hernández, Marta, Oniciuc, Elena-Alexandra, Eiros, José María, Fernández-Natal, Isabel, Wagner, Martin, Rodríguez-Lázaro, David
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2019
• Subjects: air; airports; Amino Acid Substitution; Anti-Bacterial Agents - pharmacology; Austria; Bacterial Proteins - genetics; Cheese - microbiology; cheeses; Europe; Food; Food Microbiology; Food, Preserved - microbiology; Gene Deletion; gene expression; genes; Methicillin resistant Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus - drug effects; Methicillin-Resistant Staphylococcus aureus - isolation & purification; Microbial Sensitivity Tests; MRSA; OS-MRSA; Oxacillin - pharmacology; Oxacillin-susceptible mecA-positive Staphylococcus aureus; Peptidyl Transferases - genetics; plasmids; processed foods; Promoter Regions, Genetic; Repressor Proteins - genetics; Staphylococcus aureus - drug effects; Staphylococcus aureus - genetics; Staphylococcus aureus - isolation & purification; Europe; Austria; OS-MRSA; Methicillin resistant Staphylococcus aureus; Oxacillin-susceptible mecA-positive Staphylococcus aureus; MRSA; Food
• ISSN: 0740-0020; 1095-9998; 1095-9998
• DOI: 10.1016/j.fm.2019.01.021

We report for the first time an oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) associated with a processed food product in Europe. One isolate (MRSA-ST5-type V SCCmec) was found in cheese among 600 food samples confiscated from air passengers from international flights in Vienna Airport (Austria). Type V SCCmec strains do not harbor functional mecI-mecR1 genes and in such strains mecA expression is regulated by the bla system (blaI-blaR1-blaZ). It has been recently reported that malfunctions in the bla system lead to the constitutive expression of mecA. The OS-MRSA reported in this study harbored the bla system on a plasmid and one deletion occurred in the blaR1 gene causing a frameshift variant that lead to an incomplete BlaR1 protein. This finding highlights the potential role of food as a neglected route of dissemination of emerging MRSA variants. •First characterization of OS-MRSA associated with processed food products in Europe.•Novel amino acid substitution identified in the transpeptidase domain of PBP2a.•Description of bla system carried on a plasmid.•Deletion in blaR1 gene lead to an incomplete BlaR1 protein.