The researchers claim the treatment would remove the bug's 'super' status

Methicillin-resistant Staphylococcus aureus is so-called because it is immune to the antibiotic methicillin.

But scientists at Worcestershire firm Pharmaceutica found this resistance coud be neutralised by an amino acid called glycine.

Their research is published in New Scientist magazine.

Resistant bacteria are not resistant to hand washing Dan Jernigan, US Centres for Disease Control

MRSA is estimated to cause up to 60% of all staph infections in hospitals.

Government figures suggest around 5,000 people die from MRSA-related problems every year.

But these figures have been challenged by the MRSA Support Group, which claims the true figure is probably four times higher.

The Birmingham-based organisation, which has 400 members across the UK, worked out its estimate from trawling through figures provided by the National Audit Office, the Department of Health and the House of Commons debates record Hansard.

Some strains of the bacterium are also resistant to other antibiotics, including vancomycin, the "last resort" treatment for MRSA.

Methicillin works in the same way as penicillin, by blocking bacterial enzymes called PBPs, which normally strengthen cell walls.

The first strains of Staphylococcus aureus that were resistant to the drug appeared in 1961, just two years after it was first used.

It became resistant by picking up the gene for another PBP enzyme, PBP2a, which methicillin is unable to bind to.

Mice tests

In the 1990s, Dr Michael Levey's team at Pharmaceutica found glycine significantly increased the susceptibility of 20 different strains of MRSA to methicillin.

A dose of just four milligrams of the drug per litre of blood plasma compared to 256mg/l was needed to kill the bacterium when glycine was used.

But the concentrations of the glycine compounds had to be extremely high to have this effect.

However, more recent tests by the researchers found a particular glycine compound, BT19976a, makes MRSA susceptible to antibiotics using concentrations regarded as safe.

Many of the antibiotics available to doctors cannot be used against MRSA because the doses needed would be toxic.

Methicillin is no longer produced, but Mr Levey said his research suggested giving an intravenous dose of the glycine compound should mean safe doses of the antibiotic could be used.

It is believed that the glycine compound alters the composition of the cell wall's building blocks, preventing the action of PBP2a.

Tests of the treatment on mice are under way.

But Dan Jernigan, from the US Centres for Disease Control, said: "No matter what we do, bacteria will find a way around it.

"But there are some things that always work. Resistant bacteria are not resistant to hand washing."