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US4681852A Expired / Lapsed US ⏱️ 0.0 years remaining

Novel microorganism and method

Assignee: Austgen Biojet International Pty Ltd
•
Filing: 1983-01-18
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Granted: 1987-07-21
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Expires: 2003-01-18
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Abstract

Abstract A method for producing phenylalanine comprising culturing novel strains of the bacteria Escherichia coli. The novel strains of E. coli are those in which inhibition of the enzyme DAHP synthease by phenylalanine, tyrosine or tryptophan is removed and inhibition of the enzyme chorismate mutase P-prephenate dehydratase by phenylalanine is removed and in which enhanced levels of production of the enzymes DAHP synthease, chorismate mutase P-prephenate dehydratase and shikimate kinase are achieved. The organism is preferably also modified to limit the production of alternate end products from chorismate.

Inventors

  • 👤 David E. Tribe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 23:19
CPC Classifications
C; C12; C12N; C12N15/00; C12N15/09; C12N15/11; C12N15/52; C12P; C12P13/00; C12P13/04; C12P13/22; C12P13/222; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/848; Y10S435/849

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 108 words
A strain of Escherichia coli having altered production of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase and chorismate mutase P-prephenate dehydratase (CMP-PDH), wherein (i) said DAHP synthase is not subject to feedback inhibition by phenylalanine, tryosine, or tryptophan present within the microorganism and said DAHP synthase either (a) is not subject to repression by phenylalanine, tyrosine, or tryptophan or (b) is produced in greater amount than is produced by wild type E. coli and (ii) said CMP-PDH is not subject to feedback inhibition by phenylalanine and said CMP-PDH either (a) is not subject to repression by phenylalanine or (b) is produced in a greater amount than produced by wild type E. coli.
Claim 2
Dependent Claim 108 words
A strain of Escherichia coli having altered production of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase and chorismate mutase P-prephenate dehydratase (CMP-PDH), wherein (i) said DAHP synthase is not subject to feedback inhibition by phenylalanine, tryosine, or tryptophan present within the microorganism and said DAHP synthase either (a) is not subject to repression by phenylalanine, tyrosine, or tryptophan or (b) is produced in greater amount than is produced by wild type E. coli and (ii) said CMP-PDH is not subject to feedback inhibition by phenylalanine and said CMP-PDH either (a) is not subject to repression by phenylalanine or (b) is produced in a greater amount than produced by wild type E. coli.
Claim 3
Dependent Claim 43 words
A strain of E. coli as in claim 1 having altered production of shikimate kinase wherein (i) said shikimate kinase is not repressed by phenylalanine, tyrosine, or tryptophan or (iii) the amount produced is greater than that produced by a wild-type E. coli.
Claim 4
Dependent Claim 20 words
A mutant strain of E. coli as claimed in claim 1, known as NST 37 and cataloged as ATCC 31882.
Claim 5
Dependent Claim 20 words
A mutant strain of E. coli as claimed in claim 1, known as NST 70 and cataloged as ATCC 31883.
Claim 6
Dependent Claim 20 words
A mutant strain of E. coli as claimed in claim 1, known as NST 74 and cataloged as ATCC 31884.
Claim 7
Dependent Claim 31 words
A strain of E. coli as claimed in claim 1 in which the DNA of the microorganism is such that DAHP synthase is desensitized to inhibition by both phenylalanine and tyrosine.
Claim 8
Dependent Claim 29 words
A strain of E. coli as claimed in claim 1 in which the formation of DAHP synthse is desensitized to repression by mutation of the control gene tyr R.
Claim 9
Dependent Claim 39 words
A strain of E. coli as claimed in claim 2 comprising multi-copy plasmids, each of said multi-copy plasmids having a structural gene for the production of a member of the group consisting of DAHP synthase, CMP-PDH and shikimate kinase.
Claim 10
Dependent Claim 41 words
A strain of E. coli as claimed in claim 2 in which the metabolic pathways are blocked by mutation of the gene tyr A to block production of tyrosine or mutation of the gene trp E to block production of tryptophan.
Claim 11
Independent Claim 130 words
A method for the production of phenylalanine comprising the steps of culturing a strain of E. coli having altered production of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase and chorismate mutase P-prephenate dehydratase (CMP-PDH), wherein (i) said DAHP synthase is not subject to feedback inhibition of phenylalanine, tryosine, or tryptophan present within the microorganism and said DAHP synthase either (a) is not subject to repression by phenylalanine, tyrosine, or tryptophan or (b) is produced in greater amount than is produced by wild type E. coli and (ii) said CMP-PDH is not subject to feedback inhibition by phenylalanine and said CMP-PDH either (a) is not subject to repression by phenylalanine or (b) is produced in a greater amount than produced by wild type E. coli; in a media containing a carbohydrate and recovering the phenylalanine.
Claim 12
Independent Claim 130 words
A method for the production of phenylalanine comprising the steps of culturing a strain of E. coli having altered production of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase and chorismate mutase P-prephenate dehydratase (CMP-PDH), wherein (i) said DAHP synthase is not subject to feedback inhibition of phenylalanine, tryosine, or tryptophan present within the microorganism and said DAHP synthase either (a) is not subject to repression by phenylalanine, tyrosine, or tryptophan or (b) is produced in greater amount than is produced by wild type E. coli and (ii) said CMP-PDH is not subject to feedback inhibition by phenylalanine and said CMP-PDH either (a) is not subject to repression by phenylalanine or (b) is produced in a greater amount than produced by wild type E. coli; in a media containing a carbohydrate and recovering the phenylalanine.
Claim 13
Dependent Claim 29 words
A method as claimed in claim 10 in which the carbohydrate is a member selected from the group consisting of glucose, glycerol, xylose, maltose, lactose, lactates and acetic acid.
Claim 14
Dependent Claim 31 words
A strain of E. coli as claimed in claim 1 which DNA of the microorganism has been further modified to prevent the production from chorismate of end products other than phenylalanine.

References Cited (Backward Citations)

US2973304A Cited
US3700558A Cited
US3660235A Cited
US4278765A Cited
US4371625A Cited
JPS5573868A Cited
US4407952A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-07-20 1991-01-19 1991-07-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-07-20 1995-01-19 1995-07-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-07-20 1999-01-19 1999-07-21 $7700.00 Window Closed / Lapsed

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