Ajinomoto Co., Ltd.

Tsuyoshi Osumi

Tsuyoshi Nakamatsu

Yoshio Kawahara

Osamu Kurahashi

Kazuhiko Matsui

Shinichi Sugimoto

Eiichiro Kimura

Seiko Hirano

Gen Nonaka

Yumi Matsuzaki

Naoki Akiyoshi

Kanae Nakamura

Masakazu Sugimoto

Mikiko Suga

Wataru Hibino

Mika Ito

Harufumi Miwa

Kazuhiko Totsuka

Manabu Yokomori

A plurality of primer sets are designed based on a region where conservation at the amino acid level is observed among various microorganisms for known gene sequences corresponding to a gene coding for an enzyme of the L-amino acid biosynthetic pathway derived from, preferably an enzyme that functions at a higher temperature compared with that of. PCR is performed by using the primers and chromosomal DNA ofas a template. The primers with which an amplification fragment has been obtained are used as primers for screening to select a clone containing a target DNA fragment from a plasmid library of chromosomal DNA of

Genes for heat resistant enzymes of amino acid biosynthetic pathway derived from thermophilic coryneform bacteria

A plurality of primer sets are designed based on a region where conservation at the amino acid level is observed among various microorganisms for known gene sequences corresponding to a gene coding for an enzyme of the L-amino acid biosynthetic pathway derived frompreferably an enzyme that functions at a higher temperature compared with that ofPCR is performed by using the primers and chromosomal DNA ofas a template. The primers with which an amplification fragment has been obtained are used as primers for screening to select a clone containing a target DNA fragment from a plasmid library of chromosomal DNA of

Thermophilic amino acid biosynthesis system enzyme gene of thermotolerant coryneform bacterium

Disclosed is a coryneform bacterium having resistance to azaserine or &bgr;-(2-thienyl)-DL-alanine and having L-serine productivity. Also, disclosed are D-3-phosphoglycerate dehydrogenase derived from a coryneform bacterium, in which feedback inhibition by L-serine is desensitized; the D-3-phosphoglycerate dehydrogenase, which is obtainable from a coryneform bacterium having resistance to azaserine or &bgr;-(2-thienyl)-DL-alanine and having L-serine productivity; the D-3-phosphoglycerate dehydrogenase having an amino acid sequence depicted in SEQ ID NO: 12 in Sequence Listing or the sequence including substitution, addition or deletion of one or more amino acids, wherein an amino acid residue corresponding to the 325th glutamic acid residue of the amino acid sequence in the SEQ ID NO: 12 is replaced with an amino acid other than glutamic acid; the D-3-phosphoglycerate dehydrogenase that has an amino acid sequence depicted in SEQ ID NO: 11 in Sequence Listing; a DNA coding for the D-3-phosphoglycerate dehydrogenase described above; the DNA that has a base sequence depicted in SEQ ID NO: 13 in Sequence Listing; a coryneform bacterium which harbors a recombinant DNA containing the DNA; and a method of producing L-serine, comprising the steps of cultivating the bacterium described above in a medium to allow accumulation of L-serine in the medium, and collecting the L-serine from the medium.

Method of producing L-serine by fermentation

L-serine is produced by cultivating in a medium a coryneform bacterium having L-serine productivity in which an activity of at least one of phosphoserine phosphatase and phosphoserine transaminase is enhanced, preferably, further having introduced therein a gene coding for D-3-phosophoglycerate dehydrogenase in which feedback inhibition by L-serine is desensitized, allowing L-serine to accumulate in the medium, and collecting the L-serine from the medium.

The present invention relates to a fermentation process using a L-lysine-producing microorganism having a resistance to an acyl-lysine, a methylated acyl-lysine or both an acyl-lysine and a methylated acyl-lysine. By the process of the present invention, L-lysine may be produced in high yields providing an improved process that reduces the cost of industrially produced L-lysine.

Process for producing l-lysine by fermentation employing a microorganism

Growing community of inventors

Kawasaki, Japan

Tsuyoshi Osumi