U. Minnesota Researchers Merge Fungal and Bacterial Enzymes in E. Coli for Synthesis of Commodity Chemical Isobutyric Acid

Researchers at the University of Minnesota led by Prof. Kechun Zhang have engineered a synthetic metabolic pathway using fungal and bacterial enzymes in E. coli to enable the direct biosynthesis of isobutyric acid from glucose. _GCC

GCCCombining enzymes from multiple microbes gives researchers and engineers a far wider range of reactions to work with, for synthesis of high value chemicals from biomass sugars. They can either combine the enzymes in a single organism using gene insertion techniques, or they can design bioreactors which contain multiple organisms which act on the substrate either in sequence or simultaneously.

U. Minnesota researchers designed a special E.Coli which contains both fungal and bacterial enzymes. This allows the complete synthesis of isobutyric acid to take place using only one type of organism -- a simpler arrangement in many ways.

Isobutyric acid is a high-volume commodity chemical used in the production of fibers, resins, plastics, and dyestuffs, and is used as an intermediate in the manufacture of pharmaceuticals, cosmetics, and food additives. Isobutyric acid also can be further converted to methacrylate (i.e., methacrylic acid - MAA) and methyl methacrylate (MMA) which are commodity chemicals used in the production of plexiglass (polymethyl methacrylate plastics), adhesives, ion exchange resins, textile size, leather treatment chemicals, lubrication additives and crosslinking agents.

Making methacrylate via traditional chemical synthesis techniques usually begins with either natural gas or crude oil as the feedstock. The biological pathway uses renewable sugar feedstock instead of petroleum based feedstock.

The researchers have filed for a patent on the technology, and the University of Minnesota is seeking commercialization partners. _GCC

Although cheap natural gas prices will retard the commercial implementation of such processes, this is the proper time to perfect the technologies. As natural gas prices inexorably rise due to increasing conversion of methane to liquid fuels for transportation and fuel cell use, alternative feedstocks for chemical and plastics production will then already be available to substitute economically for natural gas and petroleum.