Volume 8, Issue 1, Pages 17-31 (January 2001) Energetic, structural, and antimicrobial analyses of β-lactam side chain recognition by β- lactamases  Emilia Caselli, Rachel A Powers, Larry C Blasczcak, Chyun Yeh Earnest Wu, Fabio Prati, Brian K Shoichet  Chemistry & Biology  Volume 8, Issue 1, Pages 17-31 (January 2001) DOI: 10.1016/S1074-5521(00)00052-1

Fig. 1 Clinically used penicillins (I–V) and cephalosporins (VI–VIII) Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Fig. 2 β-Lactam hydrolysis by serine β-lactamases. The deacylation step is slow for β-lactam inhibitors and poor substrates. B represents the general base in the mechanism. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Fig. 3 Comparison between the deacylation high-energy intermediate of a penicillin in a serine β-lactamase and the transition-state analog formed by an acylglycineboronic acid and the same enzyme. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Fig. 4 Stereoview of 2Fo−Fc electron density of the refined models for AmpC complexes of (A) compound 9 and (B) compound 11. The density is contoured at 1 s. Carbon atoms are colored orange, oxygen atoms red, nitrogen atoms blue, sulfur atoms green, chlorine atoms magenta, and boron atoms purple. These figures were generated using Turbo [38]. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Fig. 6 Synergistic effects of compounds 15 and 10 observed with the β-lactam ceftazidime. (A) E. cloacae strain EB5 (β-lactamase negative). Each of the upper disks contains 25 μg ceftazidime. The lower disk on the left contains 100 μg compound 15, and the lower disk on the right contains 100 μg compound 10. (B) E. cloacae strain 265A (Group I β-lactamase hyper-producer). Each of the upper disks contains 50 μg ceftazidime. The lower disk on the left contains 100 μg of 15, and the lower disk on the right contains 100 μg of 10. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Fig. 5 Key polar interactions observed between AmpC and (A) compound 9 and (B) compound 11. Dashed yellow lines indicate hydrogen bonds. Atoms are colored as in Fig. 4, except for the inhibitors where carbon atoms are colored gray in 9 and magenta in 11. Cyan spheres represent water molecules. Interaction distances are listed in Table 4. These figures were generated with MidasPlus [39]. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Fig. 7 Overlay of the structure of cloxacillin in complex with the AmpC mutant enzyme Q120L/Y150E and of the transition-state analog 9 in complex with wild type AmpC. Carbon atoms of cloxacillin are colored green, and carbon atoms of 9 are colored gray. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Scheme 1 General scheme of synthesis of acylglycineboronic acids. See Section 4 for synthesis of boronic acids with other side chains. Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)

Chemistry & Biology 2001 8, 17-31DOI: (10.1016/S1074-5521(00)00052-1)