Background

Antibiotics represent the most effective treatment against bacterial infections. Since the discovery of penicillin by Alexander Fleming in 1928, many new antibiotics have been constantly developed and were successfully applied to treat life-threatening diseases. This significant advancement in medicine saved millions of lives and still does today. However, fighting microorganisms has never been a completed task, but rather an ongoing race between drug discovery and pathogens developing resistances. Thus, multi-drug resistant bacteria still constitute a major threat for humanity, as infectious diseases represent the second leading cause of death worldwide. [1] One major reason, for the steady increase of antimicrobial resistances is the “inappropriate use of antimicrobials”. Due to excessive prescription and application in livestock farming, little amounts of antibiotics are nearly found everywhere, even in drinking water. These low-dose and non-lethal concentrations containing habitats, allow bacteria to adjust and develop resistances. As Beta-lactams make up a large percentage of all antibiotics used, the project preferentially focused on this class of broad-spectrum antibiotics. Carbapenems, penicillin derivatives, cephalosporins and monobactams represent the four main classes of the beta-lactams that sum up to over 100 different active substances. All compounds of this particular group can be easily identified by their common chemical structure: the beta-lactam ring (see Figure1).