Enzymatic Production of Amoxicillin by β-Lactamase-deficient Mutants of Pseudomonas melanogenum KY 3987

Abstract

A search was undertaken for microorganisms that can catalyze the enzymatic production of amoxicillin. Pseudomonas melanogenum KY 3987 was selected from our stock cultures, β-Lactamase-deficient mutants were isolated from amoxicillin-sensitive mutants derived from this strain. These mutants became sensitive to other penicillins and cephalosporins as well as amoxicillin and did not produce β-lactamase even in the presence of an inducer, such as penicillin V. Amoxicillin was effectively synthesized from D-2-p-hydroxyphenylglycine methyl ester and 6-aminopenicillanic acid (6-APA) with these mutants as the enzyme sources. The conversion ratio from 6-APA to amoxicillin was about 90% as a mol ratio.