Patent EP0190921A2 successfully refreshed from Google Patents.
EP0190921A2
Expired / Lapsed
EP
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Method for the overproduction of amino acids
Assignee: Engenics Inc
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Filing: 1986-02-04
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Granted: —
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Expires: 2006-02-04
Abstract
Abstract A method is provided for overexpressing an amino acid in a microorganism comprising the step of altering the chromosomal DNA of host microorganisms or transforming the host microorganisms with at least one expression vector such that the resultant microorganism will overexpress certain operons and be inactive with respect to the other operons in the biosynthetic pathway of the amino acid, whereby overexpression of the amino acid will occur.
Inventors
- 👤 Carol Talkington
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 08:45
CPC Classifications
C; C12; C12P; C12P13/00; C12P13/04; C12N; C12N15/00; C12N15/09; C12N15/11; C12N15/52; C12N15/63; C12N15/70; C12P13/22
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
101 words
A method for overexpressing an amino acid in a microorganism comprising the step of altering the chromosomal DNA of said microorganism and/or transforming said microorganism with at least one expression vector wherein said alterations or vector causes (a) overexpression of at least one enzyme necessary for the biosynthesis of said amino acid; (b) elimination of feedback inhibition of expression of said amino acid by mutation of at least one gene necessary for the biosynthesis of said amino acid; and (c) inactivation of at least one gene which produces a product which inhibits or represses expression of said enzyme in step (a).
Claim 2
Independent Claim
101 words
A method for overexpressing an amino acid in a microorganism comprising the step of altering the chromosomal DNA of said microorganism and/or transforming said microorganism with at least one expression vector wherein said alterations or vector causes (a) overexpression of at least one enzyme necessary for the biosynthesis of said amino acid; (b) elimination of feedback inhibition of expression of said amino acid by mutation of at least one gene necessary for the biosynthesis of said amino acid; and (c) inactivation of at least one gene which produces a product which inhibits or represses expression of said enzyme in step (a).
Claim 3
Dependent Claim
11 words
A method according to claim 1 wherein said microorganism comprises bacteria.
Claim 4
Dependent Claim
24 words
A method according to claim 1 or claim 2 wherein said bacteria are selected from the group consisting of Escherichia, Bacillus, Corynebacteria and Brevibacteria.
Claim 5
Dependent Claim
12 words
A method according to claim 3 wherein said bacteria comprise Escherichia coli.
Claim 6
Dependent Claim
30 words
A method according to claim 4 wherein said overexpression is performed by subcloning the aroF operon or the pheA onto a multicopy plasmid and transforming said plasmid into E. coli.
Claim 7
Dependent Claim
24 words
A method according to claim 4 wherein said elimination of feedback inhibition is performed by a mutant pheA gene and/or a mutant aroF gene.
Claim 8
Dependent Claim
27 words
A method according to claim 4 wherein said overexpression is performed by excising the attenuator region and performing site-directed mutagenesis on the pheA operon to overproduce phenylalanine.
Claim 9
Dependent Claim
20 words
A method according to claim 5 wherein the pheA gene is subcloned onto the muticopy plasmid containing the aroF gene.
Claim 10
Dependent Claim
26 words
A method according to claim 4 wherein said inactivation is performed by mutagenizing E. coli host chromosomal DNA by transposon mutagenesis to inactivate the tyrA gene.
Claim 11
Independent Claim
17 words
A method according to any one of claims 1 to 9 wherein said amino acid comprises phenylalanine.
References Cited (Backward Citations)
No citation records indexed.
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