METHOD FOR PRODUCTION OF POLYESTER COPOLYMER USING GENETICALLY MODIFIED MICROORGANISM

摘要

The object of the present invention is to provide a method for efficiently producing a polyester copolymer consisting of 3HB and LA via microbial fermentation with the use of a sugar as a starting material. The following is provided: a method for producing a polyester copolymer consisting of 3-hydroxybutyrate and lactate, which comprises the steps of:
(1) culturing a recombinant microorganism having a protein capable of catalyzing a reaction of transferring CoA to propionic acid and/or lactate, a protein capable of catalyzing a reaction of forming acetoacetyl-CoA from two acetyl-CoA molecules, a protein capable of catalyzing a reaction of acetoacetyl-CoA reduction, and a protein capable of catalyzing a reaction of polyhydroxyalkanoate synthesis consisting of the following amino acid sequence (a) or (b) in a medium containing a carbon source:
(a) an amino acid sequence derived from the amino acid sequence shown in SEQ ID NO: 2 by substitution of at least one of the amino acids at positions 130, 325, 477, and 481 with different amino acid(s); or
(b) an amino acid sequence derived from the protein specified in (a) by additional deletion or substitution of at least one amino acid other than the amino acids at positions 130, 325, 477, and 481 or by insertion of at least one amino acid residue; and
(2) collecting the polyester copolymer from the culture product obtained in step (1). According to the production method of the present invention, a polyester copolymer consisting of 3HB and LA can be efficiently produced using an inexpensive carbon source as a starting material, and thus the production cost of a biodegradable plastic can be reduced.