New antibiotic may help treat drug-resistant infections

Researchers have discovered a "promising" new antibiotic that may help in the battle against drug-resistant infections.
A team of researchers led by Shahriar Mobashery and Mayland Chang at the University of Notre Dame, US, said the promising new antibiotic can be a vital weapon against disease as pathogens evolve to develop resistance to long-used drugs.
The antibiotic proved effective in a mouse model infected with methicillin-resistant Staphylococcus aureus (MRSA), a bacterium that emerged in hospitals in the 1960s and has spread to the larger population since the 1990s.
Mobashery and Chang adopted an unprecedented strategy in inhibiting the way the pathogen builds its cell wall.

They conducted a rapid computational screening of 1.2 million drug-like compounds that might interfere with the process, then refined the filtering in stages until they identified 118 lead compounds to test for antibacterial activity against a range of species.
The lead quinazolinone compound that emerged from these efforts underwent additional rounds of synthesis and evaluation, producing the antibiotic, which exhibited activity in a mouse infection model.

The researchers said the discovery has implications beyond MRSA as pathogens continue to evolve resistance to existing drugs.
"Antibiotics are losing effectiveness. This means that infections cannot be treated effectively. Some infections by pathogens kill as many as 50 per cent of the patients. But the problem goes way beyond this," Mobashery said.

"Without antibiotics, we could not perform many medical treatments. One could not have a hip surgery, or an athlete could not have a knee repaired," Mobashery said.
The study was published in the Journal of the American Chemical Society.