Bacteria could be stopped from hiding in 'standby mode'

E.coli bacteria

Researchers are unraveling the mystery of how bacteria switch into 'standby mode' in the human body, enabling the bugs to evade antibiotics.

Bacteria enter standby mode when they encounter adverse conditions in the body, such as when they are starved of nutrients. This enables them to shut down their metabolism, and remain in this state until conditions become more favourable.

However, because antibiotics can only efficiently kill bacteria when they are metabolically active, the drugs cannot do so once bacteria have entered standby. 

Not only does this result in patients suffering long-term, hard-to-treat infections, but it also could lead to antibiotic resistance.

“Chronic or recurrent infections are a major problem in healthcare,” said Professor Sivaramesh Wigneshweraraj, from the Department of Medicine at Imperial College London.

To combat this, scientists at Imperial are investigating how to block bacteria entering standby mode, so that they remain vulnerable to antibiotics.

New findings, published in the journal Scientific Reports, reveal that disabling a gene, called yeaG, in E. coli bacteria could potentially prevent the bugs entering this state. When the scientists created E. coli bacteria without the gene, they were unable to properly enter standby. Mouse models confirmed their findings.

“Our results provide fundamental insight into a strategy used by bacteria entering ‘standby mode’” added Professor Wigneshweraraj, who is from the MRC Centre for Molecular Bacteriology and Infection at Imperial.

“The yeaG gene is found in many other antibiotic-resistant bacteria, including Salmonella and Klebsiella bacteria” added Dr. Rita Figueira, the lead author of the study from the Department of Medicine.

Further work is now needed to identify the whole genetic pathway that the yeaG gene is a part of, says Professor Wigneshweraraj.

“If we can do this, it could pave the way to identify much-needed new approaches to combat antibiotic resistant bacteria”.

The project was funded by the BBSRC and a Wellcome Trust Investigator Award to Prof Wigneshweraraj.