Patent US1523013A successfully refreshed from Google Patents.
Patent US4942866A successfully refreshed from Google Patents.
Patent US3967651A successfully refreshed from Google Patents.
US4452890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing L-threonine by fermentation
Assignee: Ajinomoto Co Inc
•
Filing: 1982-05-10
•
Granted: 1984-06-05
•
Expires: 2002-05-10
Abstract
Abstract An L-threonine microorganism is produced by inserting a restriction endonuclease fragment of chromosomal DNA controlling α-amino-β-hydroxy valeric acid resistance from a Brevibacterium or Corynebacterium into a plasmid and transforming a Brevibacterium or Corynebacterium which is sensitive to α-amino-β-hydroxy valeric acid.
Inventors
- 👤 Takayasu Tsuchida
- 👤 Kiyoshi Miwa
- 👤 Shigeru Nakamori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:19
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
109 words
A method for producing L-threonine by fermentation which comprises aerobically culturing in an aqueous culture medium an L-threonine producing microorganism obtained by isolating a strain transformed to become resistant to α-amino-β-hydroxy-valeric acid after incorporation into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to α-amino-β-hydroxy valeric acid, of a plasmid DNA obtained from a microorganism of the genus Brevibacterium or Corynebacterium and having been inserted therein a restriction endonuclease fragment of chromosomal DNA controlling α-amino-β-hydroxy valeric acid resistance derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium which is resistant to α-amino-β-hydroxy valeric acid, and recovering L-threonine accumulated in the resulted culture liquid.
Claim 2
Independent Claim
109 words
A method for producing L-threonine by fermentation which comprises aerobically culturing in an aqueous culture medium an L-threonine producing microorganism obtained by isolating a strain transformed to become resistant to α-amino-β-hydroxy-valeric acid after incorporation into a recipient strain of the genus Brevibacterium or Corynebacterium which is sensitive to α-amino-β-hydroxy valeric acid, of a plasmid DNA obtained from a microorganism of the genus Brevibacterium or Corynebacterium and having been inserted therein a restriction endonuclease fragment of chromosomal DNA controlling α-amino-β-hydroxy valeric acid resistance derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium which is resistant to α-amino-β-hydroxy valeric acid, and recovering L-threonine accumulated in the resulted culture liquid.
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
16 words
The method of claim 1, wherein said DNA-donor strain belongs to Brevibacterium lactofermentum or Corynebacterium glutamicum.
Claim 5
Dependent Claim
22 words
The method of claim 1, wherein said DNA-donor strain is resistant to an amount of α-amino-β-hydroxyvaleric acid or more than 100 μg/ml.
Claim 6
Dependent Claim
18 words
The method of claim 1, wherein said L-threonine producing microoganism is Corynebacterium glutamicum FERM-P5973=FERM-BP119 or Brevibacterium lactofermentum FERM-P5974=FERM-BP119.
Claim 7
Independent Claim
99 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 restriction endonuclease fragment of chromosomal DNA controlling α-amino-β-hydroxy valeric acid resistance derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to α-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 α-amino-β-hydroxy valeric acid, and (d) isolating a strain transformed to become resistant to α-amino-β-hydroxy-valeric acid.
Claim 8
Independent Claim
99 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 restriction endonuclease fragment of chromosomal DNA controlling α-amino-β-hydroxy valeric acid resistance derived from a DNA-donor strain of the genus Brevibacterium or Corynebacterium resistant to α-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 α-amino-β-hydroxy valeric acid, and (d) isolating a strain transformed to become resistant to α-amino-β-hydroxy-valeric acid.
Claim 9
Dependent Claim
16 words
The method of claim 6, wherein said recipient strain belongs to Brevibacterium lactofermentum or Corynebacterium glutamicum
Claim 10
Dependent Claim
16 words
The method of claim 6, 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
18 words
The method of claim 6, wherein said L-threonine producing microorganism is Corynebacterium glutamicum FERM-P5973=FERM-BP118 or Brevibacterium lactofermentum FERM-P5974=FERM-BP119.
References Cited (Backward Citations)
US3732144A
Cited
US4347318A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-05 | 1987-12-05 | 1988-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-05 | 1991-12-05 | 1992-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-05 | 1995-12-05 | 1996-06-05 | $7700.00 | Window Closed / Lapsed |