Characterization of a β-lactamase produced in Mycobacterium fortuitum D316

Abstract
A .beta.-lactamase from Mycobacterium fortuitum D316 was purified and some physico-chemical properties and substrate profile determined. On the basis of its N-terminal sequence and of its sensitivity to .beta.-iodopenicillanate inactivation, the enzyme appeared to be a class A .beta.-lactamase, but its substrate profile was quite unexpected, since nine cephalosporins were among the eleven best substrates. The enzyme also hydrolysed ureidopenicillins and some so-called ''.beta.-lactamase-stable'' cephalosporins.