The βD484N mutant of penicillin acylase from Escherichia coli is more resistant to inactivation by substrates and can effectively perform peptide synthesis in aqueous medium

- Penicillin acylase has been stabilized to substrate inactivation by single mutation.
- Penicillin acylase mutant βD484N can effectively catalyze peptide synthesis.
- Penicillin acylase-catalyzed peptide synthesis in alkaline aqueous medium.