Monday, April 09, 2007

DNA Factories

Continued from page 1

By Emily Singer

Codon is confident that that day will soon come. It plans to use its enhanced synthesis capacity to find better enzymes for industrial processes. Since nature hasn't always come up with the most effective proteins, scientists often design a more effective enzyme by tweaking the DNA code used to make it. But it's difficult to predict in advance which tweaks will produce the best enzymes. Codon is now using its synthesis technology to carry out that process en masse--it makes millions of copies of the same genetic construct with slight variations--and then tests them to figure out which does its job best.

For example, scientists are now hot on the trail of the ideal cellulase--an enzyme that can break down cellulose in plants. More-efficient cellulases are important for producing cellulosic ethanol, which is ethanol derived from waste biomass rather than from corn starch or sugarcane, and therefore more cost-effective. "We can take the sequence for the cellulose enzyme in, say, a termite's gut, use a computer program to figure out different ways to optimize the sequence, churn out a million different versions, and then test them to find the top ten forms," says Brian Baynes, chief scientific officer and cofounder of Codon.

The same process could be used to develop protein-based drugs that can better bind to their targets or more efficiently break down a toxin in the blood. "Knowing that they can test variations of things will get molecular biologists working more like engineers," says Danner.

The company is planning to open an expanded production facility, which will operate much like any other mass-production facility, except its product will be DNA. Codon intends to build a facility, slated to open this summer, that's much larger than current needs warrant to prepare for the DNA-synthesis boom.