Ajinomoto Co., Ltd.

Shintaro Iwatani

Yoshihiro Usuda

Kazuhiko Matsui

Stephen Van Dien

Takuji Ueda

Yuichiro Tsuji

Tomoko Suzuki

Mika Moriya

Yuta Nakai

Satoshi Okutani

Yusuke Takahashi

Masaki Kobayashi

Takahiro Asano

Akihiro Watanabe

Akira Imaizumi

Yoshinori Tajima

Wataru Hibino

Masayuki Araki

Shinya Fujiki

Kazuya Kondo

Yoshihiro Ojima

Mizuho Komaki

Fumito Ohnishi

Masahito Taya

Motomu Nishioka

Stephen c/o Ajinmoto Co Inc Van Dien

An L-amino acid is produced by culturing a microorganism of the family Enterobacteriaceae which has the ability to produce an L-amino acid and which has been modified so as to increase the expression of the evgA gene, the gadE gene, and/or the ydeO gene. These genes encode a transcription factor involved in the EvgAS two-component system regulon. The culture takes place in a medium, and the L-amino acid is collected from the medium or cells.

L-amino acid-producing bacterium and a method for producing an L-amino acid

The present invention provides a method for producing an L-amino acid by fermentation by culturing a microorganism having an L-amino acid-producing ability in a liquid medium to precipitate the L-amino acid, wherein a polymer such as a water-soluble cellulose derivative, a water-soluble polyvinyl compound, a polar organic solvent-soluble polyvinyl compound, a water-soluble starch derivative, an alginic acid salt, and a polyacrylic acid salt is added to the medium.

Method for producing an L-amino acid

A method for intracellular metabolic flux analysis comprising (a) culturing cells in a medium not containing any isotope-labeled substrate to a target phase of the metabolic flux analysis, (b) adding an isotope-labeled substrate to the medium, and continuing culture and collecting samples from the medium in time course, (c) measuring isotope distribution in an intracellular metabolite contained in the samples collected in time course, (d) performing a regression analysis for measured data and calculating an isotope distribution ratio in a steady state, and (e) analyzing a metabolic flux of the cultured cells by using the calculated isotope distribution ratio.

Intracellular metabolic flux analysis method using substrate labeled with isotope

A bacterium which belongs to the Enterobacteriaceae family and has an ability to produce an L-amino acid such as L-lysine, L-threonine and L-tryptophan and is modified to enhance glutamic acid decarboxylase activity is cultured in a medium to produce and accumulate the L-amino acid in the medium or cells of the bacterium. Then, the L-amino acid is collected from the medium or the cells.

Method for production of L-amino acid

An L-amino acid can be produced by culturing an L-amino acid-producing bacterium which belongs to the Enterobacteriaceae family and which has been modified so that the expression of a yggG gene is enhanced.

L-amino acid producing bacterium and method for producing L-amino acid

A method is described for producing an L-amino acid or a nucleic acid by culturing a microorganism having an ability to produce the L-amino acid or nucleic acid in a liquid medium in a fermentation tank containing a stirring impeller, and optionally adding seed crystals to the medium as required to produce and accumulate crystals of the L-amino acid or nucleic acid in the medium, and collecting crystals of the L-amino acid or nucleic acid from the culture. The power density of the stirring impeller is controlled to be 2.4 kW/mor lower after either precipitation of the crystals or addition of the seed crystals.

Method for producing an L-amino acid or a nucleic acid

A bacterium belonging to the genuswhich has an ability to produce L-lysine or L-threonine and which is modified so that a malic enzyme does not function normally in a cell, and a method for producing L-lysine or L-threonine, comprising culturing the bacterium in a medium to produce and cause accumulation of L-lysine or L-threonine, and collecting the L-lysine or L-threonine from the medium.

Method for producing L-lysine or L-threonine

A metabolic flux affecting substance production using cells is determined by 1) creating a stoichiometric matrix based on formulas of biochemical reactions from a substrate through a desired produced substance, 2) selecting the same number of independent metabolic fluxes from all metabolic fluxes as the degree of freedom of the stoichiometric matrix as free fluxes, 3) creating a sufficient number of random combinations of the free fluxes for a statistical analysis and calculating a metabolic flux distribution from each created combination based on the stoichiometric matrix, 4) obtaining a regression equation including a minimum number of free fluxes that shows a correlation with substance production from the calculated metabolic flux distributions by a multivariate statistical analysis, and 5) determining at least one metabolic flux affecting substance production based on a coefficient in the obtained regression equation.

Method for determining metabolic flux affecting substance production

A method for determining metabolic flux distribution of a cell, which comprises the steps of: 

Method for determining metabolic flux

A bacterium belonging to the genushaving an ability to produce an L-amino acid is cultured in a medium containing fructose as a main carbon source, preferably a medium containing a carbon source composed of 30 weight % or more of fructose and 70 weight % or less of glucose, to produce and accumulate the L-amino acid in the medium, and the L-amino acid is collected from the medium.

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Kawasaki, Japan

Shintaro Iwatani