Patent EP0066129A2 successfully refreshed from Google Patents.
EP0066129A2
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EP
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Method for producing L-threonine by fermentation
Assignee: Ajinomoto Co Inc
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Filing: 1982-05-11
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Granted: —
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Expires: 2002-05-11
Abstract
Abstract New L-threonine-producing strains of the genus Brevibacterium and Corynebacterium are obtained by separating a plasmid DNA from a microorganism of the genus Brevibacterium and Corynebacterium, inserting into the plasmid DNA a fragment of chromosomal DNA derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to a-amino-p-hydroxy valeric acid to obtain a recombinant plasmid DNA, incorporating the recombinant plasmid DNA into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to α-amino-β-hydroxy valeric acid and isolating a strain transformed to become resistant to α-amino-β-hydroxy-valeric acid. By aerobically cultivating the new strains in an aqueous culture medium L-threonine may be obtained in high yields.
Inventors
- 👤 Takayasu Tsuchida
- 👤 Kiyoshi Miwa
- 👤 Shigeru Nakamori
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 09:45
CPC Classifications
C; C12; C12N; C12N15/00; C12N15/09; C12N15/63; C12N15/74; C12N15/77; C12N15/11; C12N15/52; C12P; C12P13/00; C12P13/04; C12P13/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
115 words
A method for producing L-threonine by fermentation which comprises aerobically culturing in an aqueous culture medium an L-threonine producing microorganism derived from a parent strain of the genus Brevibacterium or Corynebacterium and recovering L-threonine accumulated in tne resulted culture liquid, characterized in that a strain transformed to become resistant to a-amino-B-hydroxyvaleric acid is used, which is obtained by incorporation into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to a-amino-B-hydroxy valeric acid, of a plasmid DNA obtained from a microorganism of the genus Brevibacterium or Corynebacterium and having been inserted therein a fragment of chromosomal DNA derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to a-amino-B-hydroxyvaleric acid.
Claim 2
Independent Claim
115 words
A method for producing L-threonine by fermentation which comprises aerobically culturing in an aqueous culture medium an L-threonine producing microorganism derived from a parent strain of the genus Brevibacterium or Corynebacterium and recovering L-threonine accumulated in tne resulted culture liquid, characterized in that a strain transformed to become resistant to a-amino-B-hydroxyvaleric acid is used, which is obtained by incorporation into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to a-amino-B-hydroxy valeric acid, of a plasmid DNA obtained from a microorganism of the genus Brevibacterium or Corynebacterium and having been inserted therein a fragment of chromosomal DNA derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to a-amino-B-hydroxyvaleric acid.
Claim 3
Dependent Claim
16 words
The method of claim 1, wherein said recipient strain belongs to Brevibacterium lactofermentum or Corynebacterium glutamicum.
Claim 4
Dependent Claim
18 words
The method of claim 1 or 2, wherein said DNA-donor strain belongs to Brevibacterium lactofermentum or Corynebacterium glutamicum.
Claim 5
Independent Claim
26 words
The method of any of claims 1 to 3, wherein said DNA-donor strain is resistant to a-amino-B-hydroxyvaleric acid in an amount of more than 100 µg/ml.
Claim 6
Independent Claim
36 words
The method of any of claims 1 to 4, wherein said L-threonine producing microorganism is Corynebacterium glutamicum AJ 11682 (FERM-P 5973 = FERM BP 118) or Brevibacterium lactofermentum AJ 11683 (FERM-P 5974 = FERM BP 119).
Claim 7
Independent Claim
95 words
A method for constructing an L-threonine producing strain which comprises: (a) separating a plasmid DNA from a microorganism of the genus Brevibacterium and Corynebacterium, (b) inserting into the plasmid DNA a fragment of chromosomal DNA derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to a-amino-- β-hydroxy valeric acid to obtain a recombinant plasmid DNA (c) incorporating the recombinant plasmid DNA into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to a-amino- β-hydroxy valeric acid, and (d) isolating a strain transformed to become resistant to a-amino- β-hydroxy-valeric acid.
Claim 8
Independent Claim
95 words
A method for constructing an L-threonine producing strain which comprises: (a) separating a plasmid DNA from a microorganism of the genus Brevibacterium and Corynebacterium, (b) inserting into the plasmid DNA a fragment of chromosomal DNA derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to a-amino-- β-hydroxy valeric acid to obtain a recombinant plasmid DNA (c) incorporating the recombinant plasmid DNA into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to a-amino- β-hydroxy valeric acid, and (d) isolating a strain transformed to become resistant to a-amino- β-hydroxy-valeric acid.
Claim 9
Independent Claim
15 words
The method of Claim.6, wherein said recipient strain belongs to Brevibacterium lactofermentum or Corynebacterium glutamicum
Claim 10
Dependent Claim
18 words
The method of claim 6 or 7, wherein said DNA-donor strain belongs to Brevibacterium lactofermentum or Corynebacterium glutamicum.
Claim 11
Dependent Claim
21 words
The method of claim 6, wherein said DNA-donor strain is resistant to an amount of L-threonine of more than 1000 µg/ml.
Claim 12
Dependent Claim
29 words
The method of claim 6, wherein said L-threonine producing microorganism is Corynebacterium glutamicum AJ 11682 (FERM-P 5973 = FERM-BP 118) or Brevibacterium lactofermentum AJ 11683 (FERM-P-5974 = FERM-BP 119).
References Cited (Backward Citations)
No citation records indexed.
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