Multilocus Sequence Typing of Staphylococcus aureus

All strains were cultured on Trypticase Soy Agar with 5% Sheep Blood (bioMérieux, Marcy l’Étoile, France), and one colony was subcultured on the same agar medium for further analysis. DNA extraction was performed as previously described (Predari et al., 1991 (link)). The amplification of the seven housekeeping genes included in the MLST scheme for S. aureus was performed as previously described (Enright et al., 2000 (link); Crisóstomo et al., 2001 (link)). Sequencing was done on a 3500xL Genetic Analyser (Thermo Fisher Scientific Waltham, Massachusetts, United States), and sequence analysis was performed using SeqScape Software v3.0™ from the same company. The sequence type (ST) was determined for each strain via the PubMLST database (Jolley et al., 2018 (link))¹ or after whole-genome sequencing (wgMLST).