A comprehensive analysis of the mutational landscape determining polymyxin resistance in <i>Klebsiella pneumoniae</i>

This study provides a comprehensive overview of TCS-mediated PolR mechanisms in K. pneumoniae, highlighting the diversity and functional impact of mutations in key regulatory genes. The prevalence of IS elements, particularly in mgrB, and point mutations in mgrB, phoPQ, pmrAB and crrAB underscores the complex evolutionary pathways leading to PolR. Understanding these mechanisms is crucial for developing effective strategies to combat the spread of PolR K. pneumoniae.