article · Antibiotics
The worldwide dissemination of plasmid-borne mcr genes poses a serious threat to public health by causing resistance to colistin, a critical last-resort antibiotic. Resistance travels through clinical, agricultural, and environmental systems, aided by diverse bacterial hosts. Distinct plasmid families employ unique strategies to propagate. IncI2 plasmids maintain stability in clinical environments and livestock, IncHI2 plasmids utilise transposons to co-select for multidrug resistance, and IncX4 plasmids spread globally due to efficient, streamlined conjugation mechanisms. Furthermore, the integration of mcr genes into bacterial chromosomes by mobile genetic elements, alongside co-selection with other antibiotic classes, intensifies multidrug resistance. These dynamics highlight how food chains, environmental reservoirs, and human activities enable resistance to cross ecological niches. Mitigating this risk requires collaborative global action, targeted surveillance of high-risk plasmids, and stricter controls on agricultural colistin use.
Colistin serves as a crucial medicine of last resort when other antibiotics fail. When bacteria share resistance genes across farms, hospitals, and natural environments, standard treatments become ineffective. Understanding how these resistance genes move across different ecosystems allows health authorities to target surveillance and interventions, safeguarding vital antibiotics from becoming obsolete.
The findings could guide developers of diagnostic assays and genomic surveillance tools to monitor high-risk plasmid families such as IncI2, IncHI2, and IncX4. This could assist public health agencies, agricultural monitoring programmes, and clinical diagnostic laboratories. Because the work is an ecological and genetic review, any resulting diagnostic or surveillance products remain at an early concept stage.
AI-generated from the published abstract. Always read the original work before citing.
The global dissemination of plasmid-mediated mcr genes, which confer resistance to the last-resort antibiotic colistin, represents a critical public health challenge driven by the interplay of clinical, agricultural, and environmental factors. This review examines the genetic and ecological dynamics of mcr-bearing plasmids, focusing on their role in disseminating colistin resistance across diverse bacterial hosts and ecosystems. Key plasmid families demonstrate distinct evolutionary strategies, including IncI2, IncHI2, and IncX4. IncI2 plasmids favor stability in livestock and clinical settings. IncHI2 plasmids, on the other hand, leverage transposons to co-select for multidrug resistance, while IncX4 plasmids achieve global dissemination through streamlined, conjugation-efficient architectures. The pervasive spread of mcr genes is exacerbated by their integration into chromosomes via mobile genetic elements and co-selection with resistance to other antibiotic classes, amplifying multidrug-resistant phenotypes. Environmental reservoirs, food chains, and anthropogenic practices further facilitate cross-niche transmission, underscoring the interconnectedness of resistance under the One Health framework. Addressing this crisis requires coordinated strategies, including reducing colistin misuse in agriculture, enhancing surveillance of high-risk plasmid types, and fostering international collaboration to preserve antimicrobial efficacy and mitigate the threat of untreatable infections.
This page summarises published work. The authoritative version sits with the publisher.
DOI: 10.3390/antibiotics14050506
Is something wrong with this record? Report it or request removal.
Discussion
Have you built on this work, tried to replicate it, or seen it applied in practice? Share what you know. Verified researchers and MARATTO™ domain experts can open a discussion, and any member can reply. Contributions are reviewed before they appear.
No discussion yet. Open the first thread.
New to MARATTO™? Create a free account.
