The interaction of penicillinase with penicillins III. Comparison of exopenicillinase preparations of various origins

• Published in: Biochimica et biophysica acta. Specialized section on enzymological subjects Vol. 92; no. 3; pp. 572 - 581
• Main Authors: Citri, N., Garber, N., Kalkstein, A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 23.12.1964
• Subjects: PCMB; p-chloromercuribenzoate ( p-hydroxymercuribenzoate)
• ISSN: 0926-6569; 1878-2248
• DOI: 10.1016/0926-6569(64)90017-3

1. 1. The interaction of various penicillinases (penicillin amidohydrolase, EC 3.5.2.6) with methicillin and oxacillin has been studied. 2. 2. The K m values have been compared and found to reflect the phylogenetic and serological relationship of the penicillinases. 3. 3. Methicillin and oxacillin accelerate the inactivation of penicillinases by heat and by urea, and expose groups sensitive to iodine and to p-chloromercuribenzoate ( p-hydroxymercuribenzoate). 4. 4. The response of penicillinases from different sources to various concentrations of these analogs has been compared. 5. 5. The patterns of response are characteristic of the source of penicillinase, and essentially independent of the structure of the analog. 6. 6. A comparison of these patterns brings out subtle differences in the tertiary structure of the active sites of closely related enzymes. 7. 7. The sensitivity of such analysis is illustrated by the difference in reponse patterns of enzymically and serologically indistinguishable induced and constitutive enzyme preparations.