摘要:
Disclosed is a process for producing L-threonine, which comprises culturing an L-threonine-producing microorganism belonging to the genus Escherichia and having a resistance to at least one of L-phenylalanine and L-leucine in a medium until L-threonine is produced and accumulated in the culture, and recovering L-threonine therefrom.
摘要:
A process for the production of L-threonine by fermentation of Escherichia coli FERM BP-3756 or Escherichia coli FERM BP-4072 and a process for the production of L-isoleucine by the fermentation of Escherichia coli FERM BP-3757 is disclosed. The strains are resistant to purine analogues such as 6-dimethylaminopurine or 6-methylaminopurine.
摘要:
Disclosed is a process for producing L-isoleucine which comprises culturing in a medium a microorganism belonging to the genus Escherichia and having resistance to an isoleucine analogue and either ethionine or argonine hydroxamate and an ability to produce L-isoleucine until L-isoleucine is accumulated in the culture, and recovering L-isoleucine therefrom.
摘要:
Disclosed is a process for producing L-tryptophan which comprises culturing in a medium a microorganism belonging to the genus Corynebacterium or Brevibacterium having resistance to an aminoquinoline derivative or a phenothiazine derivative and an ability to produce L-tryptophan until L-tryptophan is accumulated in the culture and recovering L-tryptophan therefrom.
摘要:
Disclosed are a process for producing aspartase which comprises culturing a microorganism belonging to the genus Escherichia being capable of producing aspartase in a medium until aspartase is produced and accumulated in the culture, and recovering aspartase therefrom, wherein dissolved oxygen concentration of the medium is in the range of 0 to 1 ppm on the stage that microbial growth is middle and/or late logarithmic growth phase; and a process for producing L-aspartic acid which comprises converting fumaric acid and ammonia into L-aspartic acid in an aqueous medium in the presence of an enzyme source, wherein said enzyme source is a culture produced in accordance with said aspartase-producing process, cells isolated from the culture, or processed cells thereof.
摘要:
The present invention provides a process for producing an L-amino acid which comprises culturing in a nutrient medium a microorganism which is capable of producing the L-amino acid and which can not grow in a synthetic medium containing said L-amino acid as the sole nitrogen source in an amount of 5 mg/ml or below, allowing the L-amino acid to accumulate in the culture, and recovering the L-amino acid from the culture.
摘要:
The present invention provides a process for producing an L-amino acid which comprises culturing in a nutrient medium a microorganism which is capable of producing the L-amino acid and which can not grow in a synthetic medium containing said L-amino acid as the sole nitrogen source in an amount of 5 mg/ml or below, allowing the L-amino acid to accumulate in the culture, and recovering the L-amino acid from the culture.
摘要:
The present invention provides: a protein having dipeptide-synthesizing activity; DNA encoding the protein; a recombinant DNA comprising the DNA; a transformant transformed with the recombinant DNA; a process for producing the protein having dipeptide-synthesizing activity using the transformant or the like; a process for producing a dipeptide using the protein having dipeptide-synthesizing activity; and a process for producing a dipeptide using, as an enzyme source, a culture of a transformant or a microorganism which produces the protein having dipeptide-synthesizing activity or the like.
摘要:
The present invention provides a process for producing a dipeptide other than D-alanyl-D-alanine and D-alanyl-D-serine using, as an enzyme source, a culture of a microorganism having the ability to produce a protein having D-alanine-D-alanine ligase activity or a treated matter of the culture, and a process for producing a dipeptide comprising D-amino acid using, as enzyme sources, a culture of a microorganism having the ability to produce the D-amino acid or a treated matter of the culture and a culture of a microorganism having the ability to produce a protein having D-alanine-D-alanine ligase activity or a treated matter of the culture.
摘要:
A process is disclosed for producing L-glutamic acid, the process involves culturing a microorganism belonging to the genus Corynebacterium or Brevibacterium and having both an ability to produce L-glutamic acid and a resistance to .alpha.-naphthoquinoline, an antibiotic inhibiting energy metabolism or a precursor for ubiquinone biosynthesis in a nutrient medium until L-glutamic acid is accumulated in the resulting culture liquor, and recovering the L-glutamic acid therefrom.