A new study conducted by El-Halfawy and Valvano has demonstrated how resistance to antibiotics can be communicated to other less resistant bacteria through secreted chemicals. They investigated the mechanism of resistance to a bactericide, polymyxin-B (PmB), in resistant strains of Burkholderia cenocepacia, a species that causes severe infections in patients with cystic fibrosis.
They found that exposure to PmB led to resistant sub-populations of B. cenocepacia secreting a polyamine chemical, putrescine, and a protein, YceI, both of which reduce the effect of the antibiotic on the releasing bacteria. The release of these chemicals into the environment also increases the resistance of other less-resistant subpopulations of B. cenocepacia and even provides resistance to other species of bacteria in the same area that also affect the same patients, such as Pseudomonas aeruginosa, and E. coli. They propose that these chemicals act as universal bacterial “danger” message that can provide protection to an entire multi-species, multi-strain bacterial population. Future studies may be able to identify ways to interfere with the production of these chemicals and help prevent antimicrobial resistance development in these patients.