Antimicrobial drug resistance mechanisms among Mollicutes.

Abstract Representatives of the Mollicutes class are the smallest wall-less bacteria, capable of independent reproduction. They are widespread in nature, most of them are commensals and some are pathogens of humans, animals, and plants. They are also the main contaminants of cell cultures and vaccine preparations. Despite limited biosynthetic capabilities, they are highly adaptable and capable of surviving under various stress and extreme conditions, including antimicrobial selective pressure. This review describes our current understanding of antibiotic resistance (ABR) mechanisms in mollicutes. The arsenal of protective mechanisms in these smallest bacteria include point mutations, which may include non-target genes, and unique gene exchange mechanisms, contributing to transfer of ABR genes. Better understanding of mechanisms of emergence and dissemination of ABR in mollicutes is crucial to control these hypermutable bacteria and prevent the occurrence of highly ABR strains.