METHOD FOR PREPARING PHA USING BC4023 ENCODING beta;-KETOTHIOLASE DERIVED FROM BACILLUS CEREUS

摘要

A method for preparing poly(3-hydroxyalkanoates)(PHA) by using a BC4023 gene encoding beta-ketothiolase derived from Bacillus cereus is provided to improve productivity of PHA by increasing activity of enzyme synthesizing intermediates of PHA. A method for preparing short-chain-length poly(3-hydroxyalkanoates)(PHA) having carbon number of 3-5 by using a BC4023 gene encoding beta-ketothiolase derived from Bacillus cereus comprises the steps of: preparing a recombinant vector containing phaC and phaB genes synthesizing poly(3-hydroxyalkanoates)(PHA) and a BC4023 gene encoding beta-ketothiolase having the nucleotide sequence of SEQ ID NO:3; transforming a microorganism Escherichia coli with the recombinant vector; and culturing the transformed microorganism and recovering the short-chain-length PHA. A P(3HB-co-3HV)(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer is produced by culturing the transformed microorganism in a medium containing organic acid such as propionic acid or fatty acid such as valeric acid.