Cosmetic calling for the pea

The humble pea could soon be the source of plastics and ingredients for lipsticks, potash and match heads, if research at the John Innes Centre in Norwich is successful.

The products have an advantage over their industrially-made counterparts because their production avoids the use of environmentally damaging chemicals or industrial processes. Instead, the manufacture is left to the pea plant.

And because the peas are non-food crops, they could be grown on "set-aside" land, where farmers are funded not to grow crops in order to reduce the supply of cereals.

The pea was used by Gregor Mendel last century to demonstrate the simple genetic inheritance of characteristics. More than a century later, in 1990, scientists cloned the pea's famous gene which makes peas either wrinkled or smooth.

Most peas are smooth and round-sided, says Trevor Wang, a group leader at the institute, which is funded by the Biotechnology and Biological Sciences Research Council. A quarter of their make-up is protein and they are used in animal feed. But humans eat the wrinkled pea, which is sweeter.

The scientists manipulated the gene for wrinkledness. The gene controls a key event in starch synthesis, and, as a result, the proportions of starch, protein and oil in the pea.

Investigating further, the scientists discovered five different genes responsible for producing five enzymes that bring about a wrinkled seed. They have manipulated these genes to affect the quality and quantity of starch.

Pulling out a box full of peas of different colours, sizes and smoothness, a selection of the 2,500 peas at the centre, Dr Wang says: "We have now got away from using the pea as a provider of protein to the pea as a provider of starch." From there it is an easy step to the pea as an engineer of starch, modifying it at source rather than in an industrial plant. "It is the idea of using it as a bag of chemicals," he says.

Starch and modified starch are widely used in, for example, cosmetics, vitamin supplements and explosives.

The genes were mutated by attacking them with chemicals. Now that the desirable mutations have been made they can be left to pass their characteristics on normally.

Dr Wang is exploring genetic transformation, inserting foreign genes into the pea that can make it produce plastics. To make the easiest plastic would need three new genes, which have been identified. Dr Wang predicts that the plant could be ready and certified in six years.

The pea work is just one example of non-food crop breeding at the John Innes Centre. There has also been much work on oil seed rape. "It is not arrogant to say that we could do anything with oil seed rape," says Ray Mathias. For example, scientists have discovered that a mutation in the genome of oil seed rape, which has long since been bred out of the plant, causes a fatty acid to be produced that can be used for making cling film.

"There is quite a lot of work where people are using natural mutations or inducing them with radiation," says Dr Mathias. "There are 700 fatty acids in the plant and animal kingdom so in theory we could access all these."

Work is also well underway with coriander, which produces a fatty acid that can be used to produce nylon in an environmentally friendly way.

"With coriander," says Dr Mathias, "we have something really economically viable, we are pretty sure we can do it, we have got all the technology, we just require some good genetics, good fieldwork and good biology."