VATIS UPDATE Article

Researchers from the University of Western Ontario (UWO), London, have identified novel gene products, including peptides and enzymes, that can provide resistance to classes of antibiotics used to combat a range of bacterial infections, including those that cause strep throat and chlamydia. “There are certainly, in the environment, cryptic antibiotic resistance genes that have yet to be transferred to human pathogens,” said study coauthor Edward Topp, at UWO.

Researchers collected soil samples from farm plots in London, Canada, that the team had exposed to antibiotics for up to 16 years. They extracted DNA from the samples and then cloned fragments of specific sequences into a strain of E. coli sensitive to antibiotics. When the researchers put the altered E. coli in petri dishes with various antibiotics, they saw some colonies were able to grow, indicating the transfected DNA fragments conferred resistance.

Through sequencing, they identified 34 new antibiotic resistance genes. “The particularly surprising result is the discovery of a gene that encodes for an unusual small proline-rich polypeptide that confers resistance to the macrolide antibiotics, very important in human and animal medicine,” said Topp. Macrolide antibiotics are used to treat strep throat and pneumonia, as well as chlamydia and syphilis. The mechanism by which the newly identified gene confers resistance to macrolide antibiotics is not yet known.