30 August 2010

A new source of antibiotics?

The Telegraph reports that frog skins are possibly an excellent source of new antibiotics. Apparently scientists have long known that the skin of frogs contains plenty of powerful antibiotic. They haven’t been exploited so far as the substances are also often poisonous to humans.

However, a team at the United Arab Emirates University have worked out a way of modifying the chemicals to remove their harmful side-effects.

The team has already identified 100 new antibiotics including one that could fight the hospital superbug methicillin-resistant Staphylococcus aureus (MRSA) bacteria.

Frog skin is an excellent potential source of such antibiotic agents," said Dr Michael Conlon, a biochemist at the university in Abu Dhabi. "They've been around 300 million years, so they've had plenty of time to learn how to defend themselves against disease-causing microbes in the environment.”

Dr Conlon and colleagues have discovered a way to tweak their molecular structure, making them less toxic to human cells but more powerful germ killers. Similarly, the scientists also discovered other tweaks that enabled the frog skin secretions to shrug off attack by destructive enzymes in the blood.

The result was antibiotics that last longer in the bloodstream and are more likely to be effective as infection fighters, Conlon noted.
The antibiotic substances work in an unusual way that makes it very difficult for disease-causing microbes to develop resistance,

The scientists are currently screening skin secretions from more than 6,000 species of frogs for antibiotic activity. So far, they have purified and determined the chemical structure of barely 200, One substance isolated from the skin secretions of the Foothill Yellow-legged Frog — a species once common in California and Oregon but now facing extinction — shows promise for killing methicillin-resistant Staphylococcus aureus (MRSA) bacteria. MRSA is a "superbug," infamous for causing deadly outbreaks of infection among hospitalised patients.

The skin of the mink frog, likewise, contains secretions that show promise for fighting "Iraqibacter," caused by multidrug-resistant Acinetobacter baumanni.

Well there you have it. Hopefully the secretions will give rise o powerful new drugs that will replace the antibiotics that have been rendered relatively useless because of bacterial resistance. The problem is that a lot of the frogs are either rare or facing extinction.

Here’s a good argument for conservation (How many potential drugs have we lost because of our destruction of the environment) Still I wonder how easy it will be to synthesise the chemicals rather than use the original sources…


Nevin said...

This is really bad news for frogs.... in order to save humans, we are sacrificing animals... I do not even want to imagine the kind of testing that is already being done on these poor animals... :(

JD said...

sounds like witchcraft :)


jams o donnell said...

I know what you mean but if it is a case of removing secretions then hopefully no cruelty. It would require artificial synthesis to make the drugs in enough quantity though

perhaps eye of newt has properties too JD!

beakerkin said...

Alas the liver of the barfly likely has no use

jams o donnell said...

Alas not!

Ruth said...

I would have thought it was good news for frogs. The more useful they are thought to be to humans, the more effort will go into their conservation.

jams o donnell said...

Here's hoping although the drugs are going to have to be synthesised, mercifully!