Research offers new hope for antibiotic resistance
Scientists say their findings could reverse the rising tide of antibiotic resistance.
What makes some bacteria resistant to the most commonly prescribed antibiotics, and how this can be reversed, has been identified by scientists.
In a study, a team of researchers defined the relative importance of two mechanisms associated with β-lactams - a commonly prescribed group of antibiotics that includes penicillins, cephalosporins and carbapenems.
They found that, in one mechanism, bacteria restrict the entry of antibiotics into the cell. In the other, bacteria produce an enzyme, which destroys any antibiotic that gets into the cell. The latter was identified as the as the more important of the two mechanisms.
Scientists say their findings suggest that if chemicals could be developed to inhibit β-lactamase enzymes, a significant proportion of antibiotic resistance could be successfully reversed.
Building on these findings, a team from the University of Bristol studied the effectiveness of two types of β-lactamase enzyme inhibitor in a bacterium known to be highly resistant to common antibiotics.
They found both inhibitors failed consistently to protect the β-lactam antibiotic (ceftazidime) from attack by the β-lactamase enzyme. But when coupled with a different β-lactam antibiotic (aztreonam), the inhibitors worked very well - killing some of the most resistant bacteria the clinic had ever seen.
“Our bacteriology research has further demonstrated that β-lactamases are the real “Achilles heel” of antibiotic resistance in bacteria that kill thousands of people in the UK every year,” commented senior author Dr Matthew Alison from the University of Bristol.
“This is an exciting time for researchers studying β-lactamase inhibitors. At the risk of sounding like King Canute, it is the first time for a decade that there is some genuine positivity about our ability to turn back the rising tide of β-lactam antibiotic resistance.”
Veterinary practices are being urged to help owners safely dispose of any unused and expired pet medicines - not just antibiotics - during November's Animal Medicines Amnesty. 
