Next generation ESKAPE-E superbugs: identifying transmissible locus of stress tolerance and antibiotic resistance in pandemic bacterial lineages

The transmissible locus of stress tolerance (tLST) confers enhanced resilience to stressors, including chlorine-based disinfectants and heat. A systematic examination of 48,183 complete bacterial genomes representing 7,190 unique species identified tLST, including six novel variants, in 2,128 genomes spanning 46 bacterial species across 10 families. Among the analysed sequences, tLST was most common in ESKAPE-E bacteria, including highly drug-resistant pandemic lineages of Pseudomonas aeruginosa ST111 and Klebsiella pneumoniae ST20. The tLST1_AW1.7 variant was predominantly associated with F plasmids and was the most common variant in Enterobacter and Klebsiella, whereas tLST1 was near exclusive to E. coli, and tLST3a was dominant in Pseudomonas. This comprehensive mapping of tLST distribution highlights its potential significance in bacterial adaptation and persistence across diverse ecological and anthropogenically impacted niches, and has implications for infection control and eradication, waste and drinking water management, food animal and fresh produce production, and food safety.