Scientist targets fungal infections
Wed, 25 Apr 2012 09:05:00 BST
A scientist who has found a potential new target to treat fungal infections – responsible for a growing number of health problems in people with low immune system from thrush to blood infections and for many diseases in crops and animals – has been awarded a prestigious grant of nearly £400,000 to try and discover how to fight it.
Dr Tony Lewis, of the University of Portsmouth, identified a protein, Tok1, hidden in fungi. If he can unlock its secrets, it could open the door to scientists designing more effective drugs and antifungals with fewer side effects.
Dr Lewis, of the University’s School of Pharmacy and Biomedical Sciences, was awarded the grant for three years’ research by the Biotechnology and Biological Sciences Research Council(BBSRC).
He said: “Fungal cells are similar to human cells,
which makes it difficult to design drugs that don’t cause side effects, some of which can be extremely harmful.
“More alarmingly, similar to bacteria, fungal cells are becoming resistant to current antifungal treatments. It is the Holy Grail to find targets in fungi that don’t exist in humans because that would allow drugs and fungicides to be developed which don’t also harm us.
“Most fungal infections from dandruff to athlete’s foot to thrush are not life threatening, though they are annoying. It is estimated that three quarters of women are blighted by vaginal thrush at some point during their lives. However, fungal infections can also be very serious. Patients undergoing chemotherapy, treatment for HIV, or organ transplantation, have a weakened immune system which opens the way for fungal infections which can be deadly. Babies and the elderly are also high risk.”
It is estimated that up to 1.5 million people die worldwide every year due to a fungal infection.
As well as human health, the research could potentially revolutionise animal health and agriculture.
He said: “There is potential for us to integrate basic science at the University with pharmaceutical companies who make crop sprays and with NHS clinicians who treat fungal infections. Crops have been sprayed for decades but fungi are very clever and evolve quickly. They have built up resistance to lots of what we throw at them. If we knew more about their potential weaknesses we could maybe fight them better. I am hoping Tok1 will provide some useful insights.
“Tok1 is protein with a hole running through it. You can picture it looking like a Polo mint. This hole is a doorway which opens and closes and allows potassium molecules to move into and out of fungal cells. The beauty is that this protein only exists in fungi, and is not found in humans, animals or plants. It normally functions as a safety valve, closed but occasionally allowing small amounts of potassium molecules out of the cell to keep the fungus healthy.
“However, if I can work out how to keep the doorway permanently ajar this would be bad news for the fungus.”
Fungal infections are thriving in humans, animals and crops despite significant research funding being spent developing antifungal medicines. Their success in humans is thought to be due to the rapid increase in size of the immune-compromised population meaning more are at risk, combined with an increased use of antifungals and an accompanying increased resistance.