Patent US6301478B1 successfully refreshed from Google Patents.
US3770587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemically modified proteolytic enzymes
Assignee: Pfizer Inc
•
Filing: 1971-02-09
•
Granted: 1973-11-06
•
Expires: 1991-02-09
Abstract
Abstract Stabilized alkaline proteolytic enzymes having increased positive charge are prepared by contacting the native enzymes with compounds which attach additional basic and onium groups to the enzymes.
Inventors
- 👤 J Hamsher
- 👤 G Tate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:10
CPC Classifications
C; C12; C12N; C12N9/00; C12N9/96; C11; C11D; C11D3/00; C11D3/16; C11D3/38; C11D3/386; C11D3/38609; C12N9/14; C12N9/48; C12N9/50; C12N9/52; C12N9/54; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/832; Y10S435/839; Y10S435/886
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
62 words
A stabilized enzyme with increased positive charge for detergent use prepared by contacting under reaction conditions the native enzyme alkaline protease from Streptomyces rectus var. proteolyticus with ethylenimine methyl iodide ethyl iodide methyl bromide methyl acetamidate hydrochloride ethyl acetamidate hydrochloride propyl acetamidate hydrochloride butyl acetamidate hydrochloride o-methylisourea hydrogen sulfate o-ethylisourea hydrogen sulfate o-propylisourea hydrogen sulfate o-butylisourea hydrogen sulfate or ethyl imidobenzoate hydrochloride.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |