The study identified various antimicrobial resistance genes in E. coli isolates from natural water sources in upper northeast Thailand, including mcr-1, mcr-8, mcr-9, bla oxa-48-like, aac(6')-bl-cr, qepA, and oqxAB, which confer resistance to polymyxin, carbapenem, aminoglycoside, and fluoroquinolone antibiotics.