摘要 |
<p>The invention relates to a process for the preparation of L-amino acids, in particular L-threonine, in which the following steps are carried out: a) fermentation of microorganisms of the Enterobacteriaceae family which produce the desired L-amino acid and in which at least one or more of the genes of cysteine biosynthesis chosen from the group consisting of cysG, cysB, cysZ, cysK, cysM, cysA, cysW, cysU, cysP, cysD, cysN, cysC, cysJ, cysI, cysH, cysE and sbp, or nucleotide sequences which code for these, is (are) enhanced, in particular over-expressed, b) concentration of the desired L-amino acid in the medium or in the cells of the bacteria, and c) isolation of the desired L-amino acid.</p> |