Production of L-isoleucine by means of recombinant microorganisms with deregulated threonine dehydratase

US6107063A · kind A · utility

Assignee

• Forschungszentrum Jülich GmbH · DE

Inventors

• Bettina Moeckel · Goldkronach, DE
• Lothar Eggeling · Jülich, DE
• Hermann Sahm · Jülich, DE

Key dates

• Filing date: Mar 20, 1997
• Grant date: Aug 22, 2000
• Expiry date: Mar 20, 2017

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C12P13/06
• WIPO field: Biotechnology
• WIPO sector: Chemistry

Abstract

The invention relates to processes for the microbial production of L-isoleucine. To this end, in a gene in vitro of a threonine dehydratse, one or more bases in the gene region coding the enzyme's allosteric domains are exchanged in such a way that at least one amino acid in the amino acid sequence of the allosteric domains of the enzyme is replaced by another so that the enzyme is no longer inhibited by L-isoleucine feedback. Furthermore, concrete amino acid exchanges in the amino acid sequence of the enzyme are effected in a gene in vitro of a threonin dehydratase of Corynebacterium glutamicum by base exchange both outside and inside and outside the gene region coding the allosteric domains of the enzyme si that, after the transformation of such mutated threonine dehydratase genes into a threonine or L-isoleucine-producing host cell, the latter repeatedly forms L-isoleucine.