Periplasmic protease mutants of Escherichia coli
US4946783A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 14, 1987 |
| Grant date | Aug 7, 1990 |
| Priority date | — |
| Expiry date | Aug 14, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S435/849
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
This invention features a method of isolating a mutant strain of Escherichia coli, having a defective periplasmic protease, the method comprising the steps of: mutagenizing an E. coli cell, wherein the cell comprises: (a) an inner and an outer membrane, (b) a periplasmic space between the membranes, (c) a protein which in a first state is mobile, being able to move through the outer membrane and enter medium surrounding the cells, the protein in the first state being detectable in the medium, and in a second state is not mobile, remaining inside the cell, and (d) a periplasmic protease which converts the protein from the second state to the first state in the cell, and selecting a mutant cell which produces a reduced level of the detectable protein in the medium compared to the E. coli cell, wherein the mutant cell comprises the defective periplasmic protease. This invention also features mutant strains of E. coli having a defective periplasmic protease.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.