The Courier & Advertiser (Angus and Dundee)
Smart bacteria can change form to disguise itself from antibiotics
Bacteria can don a temporary disguise to avoid being detected by antibiotics, scientists say.
Researchers believe their study is the first to show that bacteria can change form in the human body, hiding the cell wall inside themselves.
The cell wall is often the antibiotic target, so concealing it means antibiotics have no target, providing a potential cause of resistance.
Scientists from Newcastle University used state-of-the-art techniques to analyse samples from elderly patients with urinary tract infections (UTI).
Lead author, Dr Katarzyna Mickiewicz, said: “Imagine that the wall is like the bacteria wearing a high-vis jacket.
“This gives them a regular shape – for example a rod or a sphere, making them strong and protecting them but also makes them highly visible – particularly to human immune system and antibiotics like penicillin.
“What we have seen is that in the presence of antibiotics, the bacteria are able to change from a highly regular walled form to a completely random, cell wall-deficient L-form state – in effect, shedding the yellow jacket and hiding it inside themselves.
“In this form the body can’t easily recognise the bacteria so doesn’t attack them, and neither do antibiotics.”
The research, known as “L-form switching”, shows that when antibiotics are present – such as in a patient with a UTI receiving penicillin or other cell wall-targeting antibiotic – the bacteria has the ability to change form.
Published in the Nature Communications journal, it used samples obtained through a collaboration with clinicians at the Newcastle Freeman Hospital.
The World Health Organisation has identified antibiotic resistance as one of the biggest threats to global health, food security, and development today.
In a previous study, the Errington lab team demonstrated that the immune system can also to some extent induce L-form switching but that antibiotic treatment has a much more profound effect.