Crystallographic studies of the - Iactamases from B . cereus
نویسنده
چکیده
The Gram-positive bacterium B. cereus produces both -lactamase I, a class A serine enzyme, and -lactamase II, a zinc dependent enzyme of class B. Crystallographic studies of these two enzymes have shown that -lactamase I is homologous with the penicillin-sensitive D-alaD-ala carboxypeptidase-transpeptidase of Streptomyces R61 while -lactamase II has a hitherto unknown structure. New methods of studying enzyme activity crystallographically promise to illuminate the mechanisms of action of these enzymes.
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