Scientists find new life, but not as we know it

Scientists may be on the verge of discovering a wholly new type of life- form, entirely distinct from the three main groups that are believed to populate the Earth at present.

The discovery of new microbes is a lucrative business. New genes, enzymes, antibiotics and other molecules are in constant demand by pharmaceutical companies. A microbe producing a useful molecule could be worth billions of pounds to a drug company.

All known life on the planet can be put into one of three groups - known as the Eubacteria Archaebacteria and the Eukaryotes. The first two are composed of microbes which are too small to be seen but form a vital environmental role.

.Microbes perform a key role in recycling nutrients and breaking down organic material, but most bacteria are not studied or classified in detail.

After a more than a century of patiently studying and classifying bacteria, only about 5,000 species have been described in any depth. Now scientists are harnessing the latest advances in molecular biology to study the bacteria at the genetic level.

At this level there are far greater differences between many microbes than between people, and say, oak trees. Classifying bacteria on the basis of the genetic differences has revealed a hitherto hidden world.

In one pool, in the Yellowstone National Park in Wyoming, Dr Norman Pace and Sue Barnes discovered 60 species using new technology.

According to research to be published in the Proceedings of the National Academy of Sciences, Dr Pace and Ms Barnes have even discovered a new kingdom of archaebacteria, as distinct as plants are to animals.

Dr Pace claims that scientists will soon discover an entirely new group of life-forms to accompany the three broad groups that exist at present. If true it will spark a minor revolution in the way that scientists classify microbes.