Supplementary data – M. iowae antimicrobial resistance genetic markers – Buni, 2026

In the presence of orthovanadate (OV), MIC values were significantly lower than in the absence of OV for spiramycin, tilmicosin, tylosin and oxytetracycline, which may indicate the presence of an active efflux system in M. iowae. Putative promoter regions of efflux-related genes were predicted and characterized. Genetic mutations, previously described in other bacteria, were described to be associated with elevated fluoroquinolone, macrolide and lincomycin MICs in M. iowae, although certain resistant phenotypes remained unexplained, promoting future examinations for deeper insights.

The developed MAMAs may support rapid identification of M. iowae strains with elevated MIC values for fluoroquinolones. The better understanding of the efflux pump mechanisms enables the development of alternative methods for the support of therapy against this pathogen.