US4675292A
Expired / Lapsed
US
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Stabilization of glucose isomerase
Assignee: Dow Chemical Co
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Filing: 1985-03-04
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Granted: 1987-06-23
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Expires: 2005-03-04
Abstract
Abstract Extracellular enzymes are stabilized with a carboxyalkylated or phosphonoalkylated polymer having a molecular weight of at least 500 Daltons. Exemplified is the stabilization of the enzyme glucose isomerase used in a process to convert D-glucose to D-fructose. In a preferred embodiment of the invention the feedstream containing the substrate is contacted initially with the stabilizer and then with the enzyme. In this system the stabilizer and enzyme are maintained in separate reactors. This separation, advantageously, results in a higher half-life for the enzyme.
Inventors
- 👤 Robert A. Houtchens
- 👤 Roberta C. Cheng
- 👤 Karen M. McCoy
- 👤 Carol C. Epstein
- 👤 Norman G. Moll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:40
CPC Classifications
C; C12; C12N; C12N9/00; C12N9/96; C12N11/00; C12N11/02; C12N11/04; C12N11/08; C12N11/082; C12N11/089; C12P; C12P19/00; C12P19/24
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
42 words
A process for stabilizing extracellular glucose isomerase used to convert D-glucose in a feedstream to D-fructose which comprises contacting said feedstream or said extracellular glucose isomerase with a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte having a molecular weight of at least 500 Daltons.
Claim 2
Dependent Claim
42 words
A process for stabilizing extracellular glucose isomerase used to convert D-glucose in a feedstream to D-fructose which comprises contacting said feedstream or said extracellular glucose isomerase with a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte having a molecular weight of at least 500 Daltons.
Claim 3
Dependent Claim
14 words
The process of claim 1 wherein said cationic polyelectrolyte is a carboxymethylated cationic polyelectrolyte.
Claim 4
Dependent Claim
21 words
The process of claim 1 wherein said glucose isomerase is produced by glucose isomerase-producing microbial cells belonging to the genus Ampullariella.
Claim 5
Dependent Claim
17 words
The process of claim 3 wherein said Ampullariella glucose isomerase-producing cells are Ampullariella species 3876, ATCC 31351.
Claim 6
Dependent Claim
45 words
The process of claim 1 wherein the alkyl of the carboxyalkylated or phosphonoalkylated moiety of said carboxyalkylated or phosphonoalkylated cationic polyelectrolyte is --(CH 2 ) n -- wherein n=1-3, or --(CHR)--(CH 2 ) n -- wherein R=methyl, ethyl, propyl, or isopropyl, and n=1 or 2.
Claim 7
Dependent Claim
12 words
The process of claim 1 wherein said extracellular glucose isomerase is immobilized.
Claim 8
Dependent Claim
12 words
The process of claim 1 wherein said extracellular glucose isomerase is encapsulated.
Claim 9
Dependent Claim
18 words
The process of claim 7 wherein the glucose isomerase is encapsulated with a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte.
Claim 10
Dependent Claim
45 words
The process of claim 8 wherein the alkyl of the carboxyalkylated or phosphonoalkylated moiety of said carboxyalkylated or phosphonoalkylated cationic polyelectrolyte is --(CH 2 ) n -- wherein n=1-3, or --(CHR)--(CH 2 ) n -- wherein R=methyl, ethyl, propyl, or isopropyl, and n=1 or 2.
Claim 11
Dependent Claim
31 words
Stabilized extracellular glucose isomerase comprising extracellular glucose isomerase and a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte having a molecular weight of at least 500 Daltons, in the presence of a glucose substrate.
Claim 12
Dependent Claim
31 words
Stabilized extracellular glucose isomerase comprising extracellular glucose isomerase and a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte having a molecular weight of at least 500 Daltons, in the presence of a glucose substrate.
Claim 13
Dependent Claim
48 words
Stabilized extracellular glucose isomerase, according to claim 10, wherein the alkyl of the carboxyalkylated or phosphonoalkylated moiety of said carboxyalkylated or phosphonoalkylated cationic polyelectrolyte is --(CH 2 ) n -- wherein n=1-3, or --(CHR)--(CH 2 ) n -- wherein R=methyl, ethyl, propyl, or isopropyl, and n=1 or 2.
Claim 14
Dependent Claim
17 words
Stabilized extracellular glucose isomerase, according to claim 10, wherein said cationic polyelectrolyte is a carboxymethylated cationic polyelectrolyte.
Claim 15
Dependent Claim
14 words
Stabilized extracellular glucose isomerase, according to claim 10, wherein the glucose isomerase is immobilized.
Claim 16
Dependent Claim
14 words
Stabilized extracellular glucose isomerase, according to claim 10, wherein the glucose isomerase is encapsulated.
Claim 17
Dependent Claim
21 words
Stabilized extracellular glucose isomerase, according to claim 14, wherein the glucose isomerase is encapsulated with a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte.
Claim 18
Dependent Claim
48 words
Stabilized extracellular glucose isomerase, according to claim 15, wherein the alkyl of the carboxylalkylated or phosphonoalkylated moiety of said carboxyalkylated or phosphonoalkylated cationic polyelectrolyte is --(CH 2 ) n -- wherein n=1-3, or --(CHR)--(CH 2 ) n -- wherein R=methyl, ethyl, propyl, or isopropyl, and n=1 or 2.
Claim 19
Dependent Claim
42 words
A process for preparing D-fructose from D-glucose which comprises initially contacting a feedstream containing D-glucose with a stabilizer comprising a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte having a molecular weight of at least 500 Daltons, and then contacting said feedstream with glucose isomerase.
Claim 20
Dependent Claim
42 words
A process for preparing D-fructose from D-glucose which comprises initially contacting a feedstream containing D-glucose with a stabilizer comprising a carboxyalkylated or phosphonoalkylated cationic polyelectrolyte having a molecular weight of at least 500 Daltons, and then contacting said feedstream with glucose isomerase.
Claim 21
Dependent Claim
11 words
The process of claim 17 wherein said glucose isomerase is immobilized.
Claim 22
Dependent Claim
11 words
The process of claim 17 wherein said glucose isomerase is encapsulated.
Claim 23
Dependent Claim
45 words
The process of claim 17 wherein the alkyl of the carboxyalkylated or phosphonoalkylated moiety of said carboxyalkylated or phosphonoalkylated cationic polyelectrolyte is --(CH 2 ) n -- wherein n=1-3, or --(CHR)--(CH 2 ) n -- wherein R=methyl, ethyl, propyl, or isopropyl, and n=1 or 2.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-22 | 1990-12-22 | 1991-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-22 | 1994-12-22 | 1995-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-22 | 1998-12-22 | 1999-06-23 | $7700.00 | Window Closed / Lapsed |