Elucidation of Conditions Allowing Conversion of Penicillin G and Other Penicillins to Deacetoxycephalosporins by Resting Cells and Extracts of Streptomyces clavuligerus NP1

• Published in: Proceedings of the National Academy of Sciences - PNAS 1998-09, Vol.95 (20), p.11544-11548
• Main Authors: Cho, Hiroshi, Adrio, José L., Luengo, José M., Wolfe, Saul, Ocran, Simeon, Hintermann, Gilberto, Piret, Jacqueline M., Demain, Arnold L.
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphate - pharmacology; Ascorbic Acid - pharmacology; Bacteria; Bioassay; Biological Sciences; Cell extracts; Cephalosporins; Cephalosporins - metabolism; Colony Count, Microbial; Dithiothreitol - pharmacology; Dry cells; Enzymes; Ferrous Compounds - pharmacology; Flasks; Interphase; Intramolecular Transferases - metabolism; Ketoglutaric Acids - pharmacology; Kinetics; Magnesium Sulfate - pharmacology; Microbiology; Penicillin; Penicillin G - metabolism; Penicillin-Binding Proteins; Penicillins - metabolism; Potassium Chloride - pharmacology; Streptomyces - cytology; Streptomyces - drug effects; Streptomyces - metabolism; Streptomyces clavuligerus; Substrate specificity
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.95.20.11544

Using resting cells and extracts of Streptomyces clavuligerus NP1, we have been able to convert penicillin G (benzylpenicillin) to deacetoxycephalosporin G. Conversion was achieved by increasing by 45× the concentration of FeSOL4 (1.8 mM) and doubling the concentration of α -ketoglutarate (1.28 mM) as compared with standard conditions used for the normal cell-free conversion of penicillin N to deacetoxycephalosporin C. ATP, MgSO4, KCl, and DTT, important in cell-free expansion of penicillin N, did not play a significant role in the ring expansion of penicillin G by resting cells or cell-free extracts. When these conditions were used with 14 other penicillins, ring expansion was achieved in all cases.