CAMBRIDGE, Mass. & LEON, Spain--(BUSINESS WIRE)--July 26, 2012--Metabolix, Inc. (NASDAQ: MBLX), an innovation-driven bioscience company focused on delivering sustainable solutions for plastics, chemicals and energy, today announced that it has signed a letter of intent (“LOI”) with Antibióticos S.A. for production of MirelTM biopolymer resin at its manufacturing facility in Leon, Spain.