On Jun. 7, 2022, the University of Oxford reported new research has found that Pseudomonas bacterium develops resistance much faster than usual to a common ﾑlast-resortﾒ antibiotic. A study published in Cell Reports revealed how populations of a bacterium called Pseudomonas respond to being treated with Colistin, a ‘last resort’ antibiotic for patients who have developed multi-drug resistant infections.

The results showed that the Pseudomonas infections quickly evolved resistance to this last-resort antibiotic ﾖ due to a gene that mutates at a rate 1,000 times higher than the ﾑnormalﾒ background rate of mutation. Mutations in this gene, known as pmrB, allowed the bacteria to evolve their resistance to Colistin.