Making yeast beefier

Yeast plays a big part in converting biomass to ethanol, but scientists at the University of California, Irvine, and Coda Genomics think it could be doing a better job.

Yeast produces ethanol as a byproduct when it ferments sugars found in plant materials.

The joint UC Irvine and Coda Genomics project aims to make that process more efficient, making a bio-engineered yeast that could use 80 to 90 percent of the sugars in biomass for ethanol production, up from about 20 percent with current technologies.

"We synthesize genes from their chemical elements. So, not cloning, not anything else, we actually make synthetic DNA," Bob Molianri, president and CEO of Coda Genomics, told the Cleantech Group.

Researchers at UC Irvine's Institute for Genomics and Bioinformatics are using Coda's gene protein production algorithms to tweak the genetic structure of Saccharomyces, a yeast species that has been used in baking and fermenting alcoholic beverages for thousands of years.

This is Coda's first venture into biofuels, but far from the first commercial application of its technology. The company, which was spun out of UC Irvine in 2004, has been serving clients in the pharmaceutical industry since its inception, including Genentech, Eli Lilly, Viventia and Invitrogen.

"Coda had basically started a business to help pharmaceutical drug discovery get their proteins to work," said Molinari.

Molinari said the cost of making synthetic DNA has gone down, much like the cost of computing power, 25 to 50-fold over the last decade.

"That's now cheap enough so that if you want to actually make a gene, sometimes it's better to synthesize it chemically and assemble it, from these little pieces of DNA, rather than actually go and find it somewhere and clone it," he said.

In its natural state, the yeast processes the glucose that grows in plant materials, but does not contain the necessary enzymes to process other sugars in biomass, such as xylose and arabinose.

The researchers are working on a version that will produce enzymes that can help it digest other sugars easily, maximizing its ethanol production.

"Somebody wants to make something in yeast, where they're cloning a gene from another organism, and we can get them, compared to the cloning product, 50 or 100-fold more protein, just by running our computer and choosing the DNA code more properly," said Molinari.

Coda's technology uses computer algorithms to design synthetic genes that self-assemble easily and generate protein in large amounts.

The company has funded $1 million of the $1.6 million research project over two years. A grant from UC Irvine is making up the balance.

Coda pays royalties and licensing fees to the university for its core technologies.

Molinari expects the first indications as to whether they can work with some of the commercial yeast strains later this year.

"One thing about synthetic biology that I like to say, and some of our knowledgeable investors say, is that it actually just speeds things up in getting proteins to work well by a factor of 10," he said.

Coda, which stands for Computationally Optimized DNA Assembly, is backed by Monitor Ventures, Life Science Angels, Tech Coast Angels and OVP Venture Partners.

OVP led a $7 million Series C round in July. Coda has raised $10 million to date.

"The first product is really an improved strain of yeast," said Molinari of the research project. But other products are possible. He said the company is looking into ways of reducing the cost of enzymes used in biofuel production.

"Those aren't enzymes that are bio-manufactured by the strain of yeast they're using, those are enzymes that are bought in bulk, dumped into the process somewhere. If you can affect the cost of that, that's a major piece of the process."