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1llb
From Proteopedia
Crystal Structure Of AmpC beta-Lactamase From E. Coli In Complex With ATMO-penicillin
Overview
beta-lactamases confer resistance to beta-lactam antibiotics such as penicillins and cephalosporins. However, beta-lactams that form an acyl-intermediate with the enzyme but subsequently are hindered from forming a catalytically competent conformation seem to be inhibitors of beta-lactamases. This inhibition may be imparted by specific groups on the ubiquitous R(1) side chain of beta-lactams, such as the 2-amino-4-thiazolyl methoxyimino (ATMO) group common among third-generation cephalosporins. Using steric hindrance of deacylation as a design guide, penicillin and carbacephem substrates were converted into effective beta-lactamase inhibitors and antiresistance antibiotics. To investigate the structural bases of inhibition, the crystal structures of the acyl-adducts of the penicillin substrate amoxicillin and the new analogous inhibitor ATMO-penicillin were determined. ATMO-penicillin binds in a catalytically incompetent conformation resembling that adopted by third-generation cephalosporins, demonstrating the transferability of such sterically hindered groups in inhibitor design.
About this Structure
1LLB is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Using steric hindrance to design new inhibitors of class C beta-lactamases., Trehan I, Morandi F, Blaszczak LC, Shoichet BK, Chem Biol. 2002 Sep;9(9):971-80. PMID:12323371 Page seeded by OCA on Sat May 3 00:02:04 2008
