MCR-1

E. coli Bacteria (7316101966)

MCR-1 (Mobilized Colistin Resistance) is a gene that confers resistance to the antibiotic colistin. Colistin is considered a last-resort antibiotic for treating infections caused by multidrug-resistant Gram-negative bacteria. The discovery of MCR-1 has raised significant concerns in the medical community due to its potential to spread colistin resistance among various bacterial species.

Discovery

MCR-1 was first identified in 2015 in Escherichia coli (E. coli) isolated from pigs, raw pork meat, and a small number of human patients in China. The gene is located on a plasmid, which is a mobile piece of DNA that can be easily transferred between different bacteria, facilitating the spread of resistance.

Mechanism of Resistance

The MCR-1 gene encodes a phosphoethanolamine transferase enzyme that modifies the lipid A component of lipopolysaccharides in the bacterial outer membrane. This modification reduces the binding affinity of colistin to the bacterial cell membrane, rendering the antibiotic ineffective.

Public Health Impact

The spread of MCR-1 is a significant public health concern because it compromises the effectiveness of colistin, which is often used as a last-line treatment for infections caused by carbapenem-resistant Enterobacteriaceae (CRE) and other multidrug-resistant organisms. The presence of MCR-1 in bacteria from both animals and humans suggests that the use of colistin in agriculture may contribute to the dissemination of this resistance gene.

Surveillance and Control

Efforts to monitor and control the spread of MCR-1 include:

• Enhanced surveillance of antibiotic resistance in both clinical and agricultural settings.
• Restricting the use of colistin in livestock to reduce selective pressure.
• Developing new antibiotics and alternative therapies to treat infections caused by MCR-1 carrying bacteria.

See Also

• Antibiotic resistance
• Multidrug-resistant bacteria
• Plasmid
• Colistin

External Links

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