Continuous production of 6-aminopenicillanic acid from penicillin by immobilized microbial cells

Summary For continuous production of 6-aminopenicillanic acid (6-APA) the microbial cells ofEscherichia coli ATCC 9637 having high penicillin amidase (penicillin amidohydrolase, E.C. 3. 5. 1. 11) activity were immobilized by entrapment in a polyacrylamide gel lattice.Enzymatic properties of penicillin amidase of the immobilizedE. coli cells were investigated and compared with those of the intact cells. With regard to optimal pH and temperature, no marked difference was observed. The heat stability was somewhat increased by immobilization of the cells.The enzyme activity of the immobilized cell column was stable, and its half-life was 17 days at 40°C and 42 days at 30°C. From the effluent of the column, 6-APA was easily obtained in a good yield.Abbreviations 6-APA 6-aminopenicillanic acid - BIS N,N-methylenebisacrylamide - DMAPN -dimethylaminopropionitrile - SV space velocity