STRAINS E. COLI VNIIGENETIKA VOLTAGE 334 RU NO.6 AND VNIIGENETIKA VOLTAGE 334 NO.7 PRODUCERSOF L-TREONITE AND METHOD FOR PREPARING THEM

摘要

A method for constructing strains which produce aminoacids comprising combining of a DNA chromosome fragment of a donor microorganism containing genes controlling the synthesis of a selected aminoacid and having a mutation destroying the negative regulation of the synthesis of this aminoacid with a vector DNA molecule to form a hybrid DNA molecule. Use is made of a vector DNA molecule capable of providing amplification of the hybrid DNA molecule. The resulting hybrid DNA molecule is used for transforming cells of the recipient strain having the mutation blocking the synthesis of the selected aminoacid in this strain and the mutation partly blocking the related step of metabolism of this aminoacid to yield the strain capable of increased productivity of the selected aminoacid.