The purification and some properties of a β-lactamase (cephalosporinase) synthesized by Enterobacter cloacae

Abstract

1. A β-lactamase has been purified from a strain of Enterobacter cloacae. 2. This enzyme is about eighty times as active against cephaloridine as against benzylpenicillin or ampicillin. 3. The enzyme has a net positive charge at pH8·0 and a molecular weight of about 14000. 4. An approximate amino acid composition of the enzyme is reported.