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US4620948A Expired / Lapsed US ⏱️ 0.0 years remaining

Purification and activity assurance of precipitated heterologous proteins

Assignee: Genentech Inc
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Filing: 1984-06-01
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Granted: 1986-11-04
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Expires: 2004-06-01
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Abstract

Abstract A process for isolating and purifying refractile proteins from host cell culture including treating the host cell culture with a buffered solution to solubilize host protein, leaving refractile protein insoluble, treating the insoluble fraction with a strongly denaturing solution containing a reducing agent to solubilize the refractile protein, and renaturing the refractile protein.

Inventors

  • 👤 Stuart E. Builder
  • 👤 John R. Ogez

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 17:09
CPC Classifications
C; C12; C12N; C12N9/00; C12N9/14; C12N9/48; C12N9/50; C12N9/64; C12N9/6421; C12N9/6478; C12N9/6481; C07; C07K; C07K1/00; C07K1/107; C07K1/113; C07K1/1133; C12N9/6424; C12N9/6456; C12N9/6462; C12Y; C12Y304/00; C12Y304/21; C12Y304/21073

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 125 words
A process for isolating, purifying and reactivating heterologous proteins which are precipitated as refractile bodies in host cells, which process comprises: (a) treating the host cell culture with a buffered solution of ionic strength suitable to solubilize protein but in which refractile heterologous protein is substantially insoluble and disrupting the cells, to form a supernatant and an insoluble fraction; (b) treating the insoluble fraction from step (a) with a strongly denaturing solution containing a reducing agent to solubilize the refractile heterologous protein; (c) replacing the strongly denaturing solution with a weakly denaturing solution containing a reducing agent; and (d) reactivating the solubilized protein by removing most or all of the weak denaturant and reducing agent in the presence of air, to produce active heterologous protein.
Claim 2
Dependent Claim 125 words
A process for isolating, purifying and reactivating heterologous proteins which are precipitated as refractile bodies in host cells, which process comprises: (a) treating the host cell culture with a buffered solution of ionic strength suitable to solubilize protein but in which refractile heterologous protein is substantially insoluble and disrupting the cells, to form a supernatant and an insoluble fraction; (b) treating the insoluble fraction from step (a) with a strongly denaturing solution containing a reducing agent to solubilize the refractile heterologous protein; (c) replacing the strongly denaturing solution with a weakly denaturing solution containing a reducing agent; and (d) reactivating the solubilized protein by removing most or all of the weak denaturant and reducing agent in the presence of air, to produce active heterologous protein.
Claim 3
Dependent Claim 22 words
The process of claim 1 wherein there is employed in step (a) a cell paste or a frozen and thawed cell paste.
Claim 4
Dependent Claim 16 words
The process of claim 1 wherein the host cell culture is a culture of E. coli.
Claim 5
Dependent Claim 27 words
The process of claim 1 wherein the heterologous protein is selected from the group consisting of hGH, pGH, bGH, bovine interferon, tPA, and FMD viral coat proteins.
Claim 6
Dependent Claim 20 words
The process of claim 1 which includes the prior step of killing the host culture with non-polar solvent or detergent.
Claim 7
Dependent Claim 27 words
The process of claim 1 which includes the step of subjecting the solution resulting from step (b) to gel permeation chromatography in the presence of reducing agent.
Claim 8
Dependent Claim 58 words
The process of claim 6 which includes the step of subjecting those fractions resulting from gel permeation chromatography which contain heterologous protein to salt removal, and treating the desalted solution with an ion exchange resin at a pH at which the heterologous protein does not adsorb to the ion exchange resin all in the presence of reducing agent.
Claim 9
Dependent Claim 23 words
The process of claim 1 wherein the buffered solution in (a) is about 0.05-2.0M in ionic strength and buffered at about pH 4-10.
Claim 10
Dependent Claim 23 words
The process of claim 8 wherein the buffered solution in (a) is about 0.4-0.6M in ionic strength and buffered at about pH 6-9.
Claim 11
Dependent Claim 19 words
The process of claim 1 wherein the strongly denaturing solution is guanidine HCl in a concentration of about 1-9M.
Claim 12
Dependent Claim 14 words
The process of claim 10 wherein the concentration of guanidine HCl is about 6-8M.
Claim 13
Dependent Claim 16 words
The process of claim 1 wherein the buffered solution of Step (a) contains a reducing agent.
Claim 14
Dependent Claim 16 words
The process of claim 1 or 13 wherein there is employed β-mercaptoethanol as the reducing agent.
Claim 15
Dependent Claim 27 words
The process of claim 1 which includes the additional step of separating host culture into broth and cell paste before carrying out Step (a) on the paste.
Claim 16
Dependent Claim 17 words
The process of claim 1 which includes additional purification steps conducted in the presence of reducing agent.
Claim 17
Dependent Claim 8 words
Protein reactivated by the process of claim 1.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-11-03 1990-05-05 1990-11-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-11-03 1994-05-05 1994-11-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-11-03 1998-05-05 1998-11-04 $7700.00 Window Closed / Lapsed

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