Production of 6-aminopenicillanic acid in aqueous two-phase systems by recombinant Escherichia coli with intracellular penicillin acylase

• Main Author: Cao, Xue-jun
• Publication Date: 2004
• Other Authors: Wu, Xing-yan, Fonseca, Luís Pina, Cabral, J. M. S., Marcos, João Carlos
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://hdl.handle.net/1822/1962
• topic: 6-aminopenicillanic acid production; Aqueous two-phase systems; Bioconversion; Recombinant E. coli A56; Penicillin acylase; Science & Technology

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%.