US4480038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Density separation of protein overproducing bacteria
Assignee: EIDP Inc
•
Filing: 1982-04-30
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Granted: 1984-10-30
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Expires: 2002-04-30
Abstract
Abstract Bacterial compositions and a method for separating protein overproducing bacteria from bacteria which do not overproduce protein. The separation makes use of an increase in density of the protein overproducing bacteria relative to that of normal bacteria.
Inventors
- 👤 Yih-Shyun E. Cheng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:37
CPC Classifications
C; C12; C12N; C12N15/00; C12P; C12P21/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
83 words
A method for separating protein overproducing E. coli bacteria from admixture with normal E. coli bacteria that do not overproduce protein the separation method being applied after bacterial growth stops, comprising fractionating the admixture, based on density difference between said bacteria, into (i) a fraction richer in protein overproducing bacteria than in normal bacteria and (ii) a fraction richer in normal bacteria than in protein overproducing bacteria, fraction (i) being at least about 0.02 g/ml more dense than fraction (ii) after growth stops.
Claim 2
Independent Claim
83 words
A method for separating protein overproducing E. coli bacteria from admixture with normal E. coli bacteria that do not overproduce protein the separation method being applied after bacterial growth stops, comprising fractionating the admixture, based on density difference between said bacteria, into (i) a fraction richer in protein overproducing bacteria than in normal bacteria and (ii) a fraction richer in normal bacteria than in protein overproducing bacteria, fraction (i) being at least about 0.02 g/ml more dense than fraction (ii) after growth stops.
Claim 3
Dependent Claim
17 words
A method according to claim 1 comprising the additional step of isolating fraction (i) from fraction (ii).
Claim 4
Dependent Claim
30 words
A method according to claim 1 or claim 2 wherein the protein is selected from the group consisting essentially of β-galactosidase, X-90, human growth hormone, human α-interferon, and chimeric β-galactosidase-proinsulin.
Claim 5
Dependent Claim
11 words
A method according to claim 3 wherein the protein is β-galactosidase.
Claim 6
Dependent Claim
11 words
A method according to claim 3 wherein the protein is X-90.
References Cited (Backward Citations)
US3072538A
Cited
US4138291A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-30 | 1988-04-30 | 1988-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-30 | 1992-04-30 | 1992-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-30 | 1996-04-30 | 1996-10-30 | $7700.00 | Window Closed / Lapsed |