'Genome mining' method in bid to find new treatments

SCIENTISTS believe they could find a "treasure trove" of potential new drugs by digging into the genes of common bacteria.

The researchers are using a new tool to "excavate" bacterial genomes - an organism's genetic make-up - in the search for treatments for serious diseases.

They have already discovered a promising new antibiotic using the "genome mining" method.

It is hoped that the approach could also be used to find other kinds of drugs, such as those to treat cancer.

The drug was extracted from the soil bug Streptomyces after the scientists found and activated a particular group of dormant genes in the microbe.

In tests, the compound made by the genes was effective against several bacterial strains including Escherichia coli (E coli).

Genome mining could be one solution to the growing problem of drug-resistant bacteria, according to the study in the journal Microbiology. Many antibiotics have become ineffective against serious conditions because of inappropriate use, meaning bacteria learn to become resistant to their effects.

The scientists behind the latest research believe they have found a way of developing treatments to tackle the problem.

Dr Eriko Takano, from the University of Groningen in the Netherlands, said: "The strategy is a powerful and innovative way of searching for new antibiotic production capabilities in bacteria.

"As bacterial infections previously considered as mild and easily curable are suddenly becoming lethal and completely unresponsive to all existing medication, it is crucial that new antibiotics are discovered at a sufficiently rapid rate."

In 2002, scientists discovered several groups of genes in one species of Streptomyces whose function was unknown.

The Dutch researchers dug deeper and removed a molecule that specifically deactivated one of the mystery gene groups. Once "awakened", the genes began to manufacture the new antibiotic.

The same technique could be used to activate dormant antibiotic production lines in other micro-organisms, such as filamentous fungi, the researchers said.

"There are several thousand other uncharacterised groups of genes that have been found recently in microbial genome sequences," said Dr Takano. "This opens up a rich treasure trove of new potential drugs for clinical use."

Aberdeen-based microbiologist Professor Hugh Pennington said there was a "desperate need" for new antibiotics.

"We have not made particularly good progress in finding new treatments," he said. "So any new way of coming up with brand new agents that affect targets we have not already targeted would be excellent news."