7qor
Structure of beta-lactamase TEM-171Structure of beta-lactamase TEM-171
Structural highlights
FunctionBLAT_ECOLX TEM-type are the most prevalent beta-lactamases in enterobacteria; they hydrolyze the beta-lactam bond in susceptible beta-lactam antibiotics, thus conferring resistance to penicillins and cephalosporins. TEM-3 and TEM-4 are capable of hydrolyzing cefotaxime and ceftazidime. TEM-5 is capable of hydrolyzing ceftazidime. TEM-6 is capable of hydrolyzing ceftazidime and aztreonam. TEM-8/CAZ-2, TEM-16/CAZ-7 and TEM-24/CAZ-6 are markedly active against ceftazidime. IRT-4 shows resistance to beta-lactamase inhibitors. Publication Abstract from PubMedThe resistance of bacteria to beta-lactam antibiotics is primarily caused by the production of beta-lactamases. Here, novel crystal structures of the native beta-lactamase TEM-171 and two complexes with the widely used inhibitor tazobactam are presented, alongside complementary data from UV spectroscopy and fluorescence quenching. The six chemically identical beta-lactamase molecules in the crystallographic asymmetric unit displayed different degrees of disorder. The tazobactam intermediate was covalently bound to the catalytic Ser70 in the trans-enamine configuration. While the conformation of tazobactam in the first complex resembled that in published beta-lactamase-tazobactam structures, in the second complex, which was obtained after longer soaking of the native crystals in the inhibitor solution, a new and previously unreported tazobactam conformation was observed. It is proposed that the two complexes correspond to different stages along the deacylation path of the acyl-enzyme intermediate. The results provide a novel structural basis for the rational design of new beta-lactamase inhibitors. Crystal structures of the molecular class A beta-lactamase TEM-171 and its complexes with tazobactam.,Grigorenko VG, Petrova TE, Carolan C, Rubtsova MY, Uporov IV, Pereira J, Chojnowski G, Samygina VR, Lamzin VS, Egorov AM Acta Crystallogr D Struct Biol. 2022 Jul 1;78(Pt 7):825-834. doi: , 10.1107/S2059798322004879. Epub 2022 Jun 7. PMID:35775982[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|