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β-lactams represent the most widely used group of antibiotics with broad spectrum of antibacterial activity. However, most bacteria can develop antibiotic resistance, typically caused by beta-lactamase enzymes. Existing inhibitors of beta-lactamases can prevent antibiotic degradation arising from beta-lactam ring hydrolysis, but due to the additional development of resistance to these compounds, they are not sufficiently effective. Thus, the identification of new inhibitors and new mechanisms of lactamase inhibition is a priority. To address this challenge, we computationally screened 8 million organic molecules using the ViCi software (http://www.embl-hamburg.de/vici), which we specially developed for this purpose. The software permits the rapid screening against a known inhibitor template and selects the closest matching compounds in terms of shape and electrostatic composition. Four known low-affinity lactamase inhibitors were given to the software as a starting point. Despite the ubiquity of the various strains of beta-lactamase, access to the full set of characterized clinical samples is a big problem. Biobank of recombinant strains of E.coli - producing a variety of class A beta-lactamases, and efficient expression system for production of the recombinant class A beta-lactamases in E.coli cells have been elaborated in order to permit their study in vitro and in vivo. Recombinant TEM-1 enzyme was produced and used to assay the top compounds suggested by ViCi screening. Two new potential inhibitors bound to the allosteric site of TEM-1 were identified, both having an order of magnitude higher in vitro affinity for the enzyme than their template. To further develop the identified lead compounds we look for ways of increasing their solubility and reducing their expected toxicity. Chemical design and modification of the lead compounds as well as their in vitro tests are now in progress. X-ray crystal structure determination of the native enzyme and its complexes with ligands is the next step in testing of proposed inhibitors. The crystal structure of recombinant TEM-1 lactamase has been solved to a resolution of 2.0 Å. The ViCi software will then be used to identify compounds for the next iteration of screening. Docking protocols, validated by crystallography, will also be used to refine the results, aiding our rapid convergence to more avidly binding compounds. The current status of the X-ray crystallographic, computational and laboratory studies will be presented.