Acknowledgements The authors gratefully acknowledge
the financial support grant 2005/55079-4; 2008/52819-5 and 2013/02632-4, São Paulo Research Foundation IKK inhibitor (FAPESP) and Dr. Paloma Liras (Facultad de Ciencias Biológicas y Ambientales, Universidad de León, León, Spain) for kindly donating E. coli ESS 2235, a test organism supersensitive to beta-lactam antibiotics. References 1. Challis GL, Hopwood DA: Synergy and contingency as driving forces for the evolution of multiple secondary metabolite production by Streptomyces species. Proc Natl Acad Sci U S A 2003, 100:14555–14561.PubMedCentralPubMedCrossRef 2. Omstead DR, Hunt GH, Buckland BC: Commercial production of cephamycin antibiotics. In Comprehensive biotechnology. Edited by: Moo-Young
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