Production of 6-aminopenicillanic acid in aqueous two-phase systems by recombin...

• Author(s): Cao, Xue-jun ; Wu, Xing-yan ; Fonseca, Luís Pina ; Cabral, J. M. S. ; Marcos, João Carlos
• Date: 2004
• Persistent ID: http://hdl.handle.net/1822/1962
• Origin: RepositóriUM - Universidade do Minho
• Subject(s): 6-aminopenicillanic acid production; Aqueous two-phase systems; Bioconversion; Recombinant E. coli A56; Penicillin acylase
• Document Type: Article
• Language: English

Description

Bioconversion of Penicillin G in PEG 20000-Dextran T 70 aqueous two-phase systems was achieved using the recombinant Escherichia coli A56 (ppA22) with intracellular penicillin acylase as catalyst. The best conversion conditions were attained for: 7%(w/v) substrate (penicillin G), enzyme activity in bottom phase 52 U/ml, pH 7.8, temperature 37°C, reaction time 40 min. Five repeated batches could be performed in these conditions. Conversions ratios between 0.902-0.985mol of 6-aminopenicillanic acid (6-APA) per mol of penicillin G, were obtained and specific productivity was 3.6-4.6 μmol/min•ml. In addition the product 6-APA could directly be crystallized from the top phase with a purity of 96.2%.