A businesswoman who became a scientist as a mature student has raised £750,000 to develop an idea that could become a weapon against the MRSA superbug, the bacteria that has caused concern in Britain's hospital wards because it cannot be countered by normal antibiotics.

Heather Fairhead has only a skeleton staff of researchers at Phico Therapeutics, but the firm has patented proteins that could prove effective in fighting bacteria after the completion of clinical trials.

The proteins are versions of naturally occurring "Sasp" that the company has genetically engineered to bind to bacterial DNA and kill the organism. They are introduced to the germ by using bacteriophages - that is, viruses that only attack bacteria, which are commonly used in eastern Europe as antibiotics.

Dr Fairhead is using a bacteriophage that will target the MRSA superbug and can be applied as a cream on the skin to prevent infection or injected into a patient who has become host to the bacteria as a treatment.

Yesterday it was announced that Dr Fairhead's company has raised some £750,000 from business "angels" - including Cambridge Capital Group and Providence Investment Company.

Because such treatments take a long time to develop and gain regulatory approval, any therapy would be years away, and the company has pencilled in 2005 to begin the process of human clinical trials. But the fundraising will allow it to get closer to that stage.

Dr Fairhead started her degree in molecular microbiology at 25. She gained a doctorate and has worked at various research facilities, including Cambridge University and the University of Connecticut.

In 2000 she had the idea to commercialise the science she was studying and initially gained seed funding from business angels and the government to start Phico.

Before she started studying for her degree in 1989 she worked in marketing and ran her own small business, producing printed stationery.