Preparing L-threonine using bacteria of Enterobacteriaceae family which produces L-threonine, by culturing bacterium in nutrient medium comprising source of carbon, nitrogen and phosphorus, to produce L-threonine

摘要

Preparing (M1) L-threonine using bacteria of Enterobacteriaceaefamily which produces L-threonine, by inoculating and culturing the bacterium in a first nutrient medium, abstracting some of the fermentation broth, adding other nutrient media comprising source of carbon, nitrogen and phosphorus, to allow the formation of L-threonine. Preparing (M1) L-threonine using bacteria of the Enterobacteriaceaefamily which produces L-threonine, involves inoculating and culturing the bacterium in a first nutrient medium, abstracting some of the fermentation broth, where more than in 90 vol.% of the total volume of the fermentation broth remains in the fermentation container, then the remaining fermentation broth is topped up with one or more further nutrient media comprising at least one source of carbon, nitrogen and phosphorus, and the cultivation is continued under conditions which allow the formation of L-threonine, carrying out abstracting and nutrient broth topping step several times, and adjusting the concentration of the carbon source to a maximum of 30 g/l during cultivation. An independent claim is also included for saccharose-utilizing transconjugants of E.coliK-12 deposited as DSM 16293 at German collection of microorganisms and cell cultures.