University of Saskatchewan researchers develop new way of combating antibiotic resistance

A University of Saskatchewan research team has discovered a way to prevent bacteria from developing resistance to antibiotics, potentially helping to blunt the edge of a looming threat to public health around the world.

The University of Saskatchewan research team, led by biochemist Ron Geyer, looked at the “SOS response,” which happens when bacteria are attacked by antibiotics. The bacterial cell stops its normal cycle in order to repair its DNA. The process is quite error-prone, so there are a lot of mutations—plus the response allows the bacteria to pick up genes from other bacteria in a process called horizontal gene transfer.

Geyer and his team looked at the molecular “switching system” for the SOS response—the RecA enzyme that turns it on, and the LexA enzyme that keeps it turned off. The team developed compounds that inhibit the RecA “on” switch. This prevented the SOS response, made the antibiotics more effective, reduced mutations, and blocked horizontal gene transfer.

The team tested the RecA inhibitors both with a variety of lab bench assays and in mice against several bacteria, including two that are notorious for multi-drug resistance: Pseudomonas aeruginosa and Staphylococcus aureus.

“Our results suggest the inhibitors should be useful with a broad spectrum of bactericidal antibiotics in Gram-negative or Gram-positive bacteria,” Geyer says. He cautioned that much work remains to be done, for example, to tailor methods to better deliver RecA inhibitors.

The University of Saskatchewan has applied for a patent for the RecA inhibitor technology and is currently seeking partners to license and develop it. The work is supported by the Natural Sciences and Engineering Research Council of Canada.

Read the full news article in Infection Control Today

Read the journal article in Cell Chemical Biology, Vol 23 Issue 3