Investor Relations

PRESS RELEASE May 2003
Marcia Miller, Director of Marketing
Metabolix, Inc., 303 Third St.
Cambridge, MA 02142
617-492-0505 x227; fax: 617-492-1996
miller@metabolix.com

Dramatic improvements in the efficiency of microbial fermentations, which will reduce the cost of PHA plastics and increase their use as an alternative for petroleum-based plastics used today, is the promised outcome thanks to an award received by Metabolix, Inc. from the U.S. Department of Commerce's Advanced Technology Program (ATP). The award - totaling more than $1.6 million - will allow Metabolix scientists to reengineer the central metabolism of E. coli for highly efficient conversion of renewable sugars into PHA plastics.

The overall effect will be to reduce U.S. dependence on petrochemical feedstocks such as oil and natural gas, increase demand for U.S. agricultural products, and reduce greenhouse gas emissions - all good news for the environment. In addition, the new metabolic engineering methods will be applicable to fermentation processes for making a wide variety of other chemical products.

Metabolix's PHAs are a broad and versatile family of plastics, ranging in properties from rigid to highly elastic, and suitable for film, fiber, adhesives, coatings, molded goods, and blending with other plastics. "This ATP award will help achieve dramatic improvements in the efficiency of microbial fermentations as a whole," said Dr. Oliver Peoples, Metabolix's Chief Scientific Officer. "This means lower costs for PHAs, making them cost competitive with large volumes of plastics used in the world today."

The ATP program, part of the National Institute of Standards and Technology (NIST), provides cost-shared funding to industry-led teams which can include non-profits and universities to help advance particularly challenging, high-risk R&D projects that have the potential to spark important, broad-based economic or social benefits for the United States. The program supports projects that industry cannot fully fund on its own because of significant technical risks. ATP awards are made on the basis of rigorous competitive peer review considering scientific and technical merit of each proposal. The program accelerates enabling technology research, but does not support product development work.

Founded in 1992, Metabolix, Inc. uses sophisticated biotechnology to produce environmentally friendly performance plastics and specialty chemicals from renewable resources. The company is a world leader in applying the advanced tools of metabolic engineering and molecular biology to efficiently produce PHA plastics in microbial systems via fermentation and, ultimately, directly in non-food plant crops. The company's current focus is on commercializing PHAs in applications where they provide unique performance benefits. Targets include paper coatings, nonwovens, adhesives, disposable food ware, and performance additives for other polymers.

For more information on Metabolix, contact Marcia Miller, Director of Marketing, or visit our website at www.metabolix.com. Further information about the ATP program is available at www.atp.nist.gov