MICROBIOLOGICAL PRODUCTION OF L-THREONINE FROM HOMOSERINE

摘要

An aqueous culture medium is prepared containing preferably ethanol and/or glucose as carbon sources and inorganic salts and 0-l-20 w/v of L- or DL-homoserine; cells of biotin requiring microorganism of genus Brevibacterium, exemplified as 4 strains of Brevibacterium flavum, ammonigenes or divaricatum,or an immobilized form of these cells are added and they provide enzyme to convert the homoserine to L-threonine by racemization during cultivation at 20 to 50 DEG C for l0 to 72 hours; L-threonine is separated and purified. The homoserine can be obtained as residue from enzymatic racemization of DL-homoserine using e.g. a Pseudomonas putida strain.