Muteins of .beta.-galactosidase fragments having increased activity
US5492813A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 1993 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Nov 1, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S435/963
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Muteins of enzyme acceptor polypeptide fragments of .beta.-galactosidase are provided which exhibit substantially increased kinetic complementation activity with no significant loss in stability. A preferred enzyme acceptor fragment has an amino acid other than cysteine located at position 500 of the natural sequence. An especially preferred substitution is serine or valine. Other preferred muteins have an amino acid other than methionine located at position 443, with leucine being especially preferred, or an amino acid other than cysteine at position 76, with leucine being an especially preferred substitution. Also provided are methods for producing the novel muteins, reagent compositions comprising the novel muteins, and immunoassay methods for determining an analyte in which the novel mutein recombines with an enzyme donor polypeptide fragment to form enzymatically active .beta.-galactosidase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.