US4268632A
Expired / Lapsed
US
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Process for isolation of ribulose 1,5-diphosphate carboxylase from plant leaves
Assignee: Leaf Proteins Inc
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Filing: 1979-09-24
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Granted: 1981-05-19
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Expires: 1999-09-24
Abstract
Abstract Described herein is a process for isolating the enzymatic protein ribulose 1,5-diphosphate carboxylase from the green leaves of plants. In the process, which is particularly suited to obtaining the protein from tobacco, the leaves are ground or otherwise pulverized in the presence of a reducing agent, followed by heating the resulting pulp to about 50° C. A liquid portion containing the desired protein is separated from the pulp and then cooled to cause the crystallization of the ribulose 1,5-diphosphate carboxylase. After separation of the crystalline material, the supernatant is acidified to yield lower molecular weight proteins.
Inventors
- 👤 Samuel G. Wildman
- 👤 Prachuab Kwanyuen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:29
CPC Classifications
C; C12; C12N; C12N9/00; C12N9/88; A; A23; A23J; A23J1/00; A23J1/006; A23J1/007; Y; Y10; Y10S; Y10S435/00; Y10S435/814; Y10S435/816
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
97 words
A process for obtaining ribulose 1,5-diphosphate carboxylase from plant material comprising the leaves of green plants comprising the steps: (a) converting the leaves to a pulp comprising a mixture of a solid portion and a liquid portion, said liquid portion containing dissolved ribulose 1,5-diphosphate carboxyase; (b) heating the liquid portion to a temperature below that at which protein in the liquid portion denatures for a time sufficient to induce the ribulose 1,5-diphosphate carboxylase to crystallize when said liquid portion is cooled; and (c) cooling said liquid portion to a temperature at which said ribulose 1,5-diphosphate carboxylase crystallizes.
Claim 2
Dependent Claim
97 words
A process for obtaining ribulose 1,5-diphosphate carboxylase from plant material comprising the leaves of green plants comprising the steps: (a) converting the leaves to a pulp comprising a mixture of a solid portion and a liquid portion, said liquid portion containing dissolved ribulose 1,5-diphosphate carboxyase; (b) heating the liquid portion to a temperature below that at which protein in the liquid portion denatures for a time sufficient to induce the ribulose 1,5-diphosphate carboxylase to crystallize when said liquid portion is cooled; and (c) cooling said liquid portion to a temperature at which said ribulose 1,5-diphosphate carboxylase crystallizes.
Claim 3
Dependent Claim
23 words
A process according to claim 1 wherein the liquid portion is heated prior to its separation from the solid portion of the pulp.
Claim 4
Dependent Claim
22 words
A process according to claim 2 wherein said heating is at a temperature of from about 48° C. to about 52° C.
Claim 5
Dependent Claim
23 words
A process according to claim 3 wherein said liquid portion is cooled to a temperature at or below room temperature after said heating.
Claim 6
Dependent Claim
27 words
A process according to claim 1 wherein the liquid portion and suspended green pigmented material is separated from said pulp prior to said liquid portion being heated.
Claim 7
Dependent Claim
22 words
A process according to claim 5 wherein said heating is at a temperature of from about 48° C. to about 52° C.
Claim 8
Dependent Claim
23 words
A process according to claim 6 wherein said green pigmented material is separated from said liquid portion after heating of the liquid portion.
Claim 9
Dependent Claim
23 words
A process according to claim 7 wherein said liquid portion is cooled to a temperature at or below room temperature after said heating.
Claim 10
Dependent Claim
52 words
A process according to claim 1 wherein conversion of said leaves to a pulp is accomplished in the presence of a reducing agent, said reducing agent being employed in an amount sufficient to suppress oxidation of amino acid substituent groups comprising part of the structure of proteins present in said liquid portion.
Claim 11
Dependent Claim
12 words
A process according to claim 9 wherein said reducing agent is 2-mercaptoethanol.
Claim 12
Dependent Claim
25 words
A process according to claims 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 wherein said ribulose 1,5-diphosphate carboxylase crystallizes as octagonal crystals.
Claim 13
Dependent Claim
43 words
A process according to any of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 comprising the additional steps of separating the crystallized ribulose 1,5-diphosphate carboxylase from said liquid portion and acidifying said liquid portion to precipitate Fraction 2 protein.
Claim 14
Dependent Claim
9 words
Ribulose 1,5-diphosphate carboxylase in the form of octagonal crystals.
Claim 15
Dependent Claim
9 words
Ribulose 1,5-diphosphate carboxylase in the form of octagonal crystals.
Claim 16
Dependent Claim
22 words
A process according to claims 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wherein the leaves are tobacco leaves.
Claim 17
Dependent Claim
32 words
A process according to claims 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wherein the leaves are tobacco leaves and wherein said ribulose 1,5-diphosphate carboxylase crystallizes as octagonal crystals.
Claim 18
Dependent Claim
59 words
A process according to claims 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wherein the leaves are tobacco leaves, said ribulose 1,5-diphosphate carboxylase crystallizes as octagonal crystals and wherein the process comprises the additional steps of separating the crystallized ribulose 1,5-diphosphate carboxylase from said liquid portion and acidifying said liquid portion to precipitate Fraction 2 protein.
Claim 19
Dependent Claim
101 words
A process for obtaining ribulose 1,5-diphosphate carboxylase from tobacco plant material comprising the steps: (a) converting the plant material to a pulp comprising a mixture of a solid portion and a liquid portion, the liquid portion containing dissolved ribulose 1,5-diphosphate carboxylase; (b) heating the pulp to a temperature below that at which the protein in the liquid portion denatures for a time sufficient to induce the ribulose 1,5-diphosphate carboxylase to crystallize when said liquid portion is cooled; (c) separating the liquid portion from the solid portion; and (d) cooling the liquid portion to a temperature at which said ribulose 1,5-diphosphate crystallizes.
Claim 20
Dependent Claim
101 words
A process for obtaining ribulose 1,5-diphosphate carboxylase from tobacco plant material comprising the steps: (a) converting the plant material to a pulp comprising a mixture of a solid portion and a liquid portion, the liquid portion containing dissolved ribulose 1,5-diphosphate carboxylase; (b) heating the pulp to a temperature below that at which the protein in the liquid portion denatures for a time sufficient to induce the ribulose 1,5-diphosphate carboxylase to crystallize when said liquid portion is cooled; (c) separating the liquid portion from the solid portion; and (d) cooling the liquid portion to a temperature at which said ribulose 1,5-diphosphate crystallizes.
Claim 21
Dependent Claim
22 words
A process according to claim 17 wherein the pulp is heated to a temperature from about 48° C. to about 52° C.
Claim 22
Dependent Claim
16 words
A process according to claim 17 wherein said plant material comprises the leaves of said tobacco.
Claim 23
Dependent Claim
18 words
A process according to claim 19 wherein said plant material comprises the leaves and stalk of said tobacco.
Claim 24
Dependent Claim
22 words
A process according to claim 19 wherein the pulp is heated to a temperature from about 48° C. to about 52° C.
Claim 25
Dependent Claim
22 words
A process according to claim 20 wherein the pulp is heated to a temperature from about 48° C. to about 52° C.
Claim 26
Dependent Claim
40 words
A process according to claim 17 wherein a reducing agent is added to said plant material in an amount sufficient to suppress oxidation of amino acid substituent groups comprising part of the structure of proteins present in said liquid portion.
Claim 27
Dependent Claim
12 words
A process according to claim 23 wherein said reducing agent is 2-mercaptoethanol.
Claim 28
Dependent Claim
23 words
A process according to claim 23 wherein said reducing agent is added to the plant material prior to its conversion to said pulp.
Claim 29
Dependent Claim
36 words
A process according to claims 23, 24 or 25 wherein the plant material comprises the leaves of said tobacco and wherein the pulp is heated to a temperature from about 48° C. to about 52° C.
Claim 30
Dependent Claim
24 words
A process according to claims 17, 18, 19, 20, 21, 22, 23, 24 or 25 wherein said ribulose 1,5-diphosphate carboxylase precipitates as octagonal crystals.
References Cited (Backward Citations)
No citation records indexed.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1984-05-18 | 1984-11-17 | 1985-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-18 | 1988-11-17 | 1989-05-19 | $3760.00 | Window Closed / Lapsed |
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