Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media
US5741691A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Jan 23, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC12N9/18
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
A method for isolating and identifying modified para-nitrobenzyl esterases which exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.