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8isq
From Proteopedia
(Difference between revisions)
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| - | '''Unreleased structure''' | ||
| - | + | ==Crystal structure of extended-spectrum class A beta-lactamase, CESS-1 E166Q acylated by ampicillin== | |
| + | <StructureSection load='8isq' size='340' side='right'caption='[[8isq]], [[Resolution|resolution]] 2.24Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[8isq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Stenotrophomonas_sp._KCTC_12332 Stenotrophomonas sp. KCTC 12332]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8ISQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8ISQ FirstGlance]. <br> | ||
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.24Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BTB:2-[BIS-(2-HYDROXY-ETHYL)-AMINO]-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>BTB</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=ZZ7:(2R,4S)-2-[(R)-{[(2R)-2-AMINO-2-PHENYLACETYL]AMINO}(CARBOXY)METHYL]-5,5-DIMETHYL-1,3-THIAZOLIDINE-4-CARBOXYLIC+ACID'>ZZ7</scene></td></tr> | ||
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=8isq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8isq OCA], [https://pdbe.org/8isq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8isq RCSB], [https://www.ebi.ac.uk/pdbsum/8isq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8isq ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/A0A126NGE0_9GAMM A0A126NGE0_9GAMM] | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | OBJECTIVES: Stenotrophomonas spp. intrinsically resistant to many beta-lactam antibiotics are found throughout the environment. CESS-1 identified in Stenotrophomonas sp. KCTC 12332 is an uncharacterized class A beta-lactamase. The goal of this study was to reveal biochemical and structural characteristics of CESS-1. METHODS: The hydrolytic activities of CESS-1 towards penicillins (penicillin G and ampicillin), cephalosporins (cephalexin, cefaclor, and cefotaxime), and carbapenems (imipenem and meropenem) was spectrophotometrically monitored. Structural information on E166Q mutants of CESS-1 acylated by cefaclor, cephalexin, or ampicillin were determined by X-ray crystallography. RESULTS: CESS-1 displayed hydrolytic activities toward penicillins and cephalosporins, with negligible activity toward carbapenems. Although cefaclor, cephalexin, and ampicillin have similar structures with identical R1 side chains, the catalytic parameters of CESS-1 toward them were distinct. The k(cat) values for cefaclor, cephalexin, and ampicillin were 1249.6 s(-1), 204.3 s(-1), and 69.8 s(-1), respectively, with the accompanying K(M) values of 287.6 muM, 236.7 muM, and 28.8 muM, respectively. CONCLUSIONS: CESS-1 was able to discriminate between cefaclor and cephalexin with a single structural difference at C3 position: -Cl (cefaclor) and -CH(3) (cephalexin). Structural comparisons among three E166Q mutants of CESS-1 acylated by cefaclor, cephalexin, or ampicillin, revealed that cooperative positional changes in the R1 side chain of substrates and their interaction with the beta5-beta6 loop affect the distance between Asn170 and the deacylating water at the acyl-enzyme intermediate state. This is directly associated with the differential hydrolytic activities of CESS-1 toward the three structurally similar beta-lactam antibiotics. | ||
| - | + | Characterization of the extended substrate spectrum of the class A beta-lactamase CESS-1 from Stenotrophomonas sp. and structure-based investigation into its substrate preference.,Jeong BG, Kim MY, Jeong CS, Do H, Hwang J, Lee JH, Cha SS Int J Antimicrob Agents. 2024 Apr 7;63(6):107171. doi: , 10.1016/j.ijantimicag.2024.107171. PMID:38588869<ref>PMID:38588869</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| + | <div class="pdbe-citations 8isq" style="background-color:#fffaf0;"></div> | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Stenotrophomonas sp. KCTC 12332]] | ||
| + | [[Category: Cha SS]] | ||
| + | [[Category: Do HW]] | ||
| + | [[Category: Jeong BG]] | ||
| + | [[Category: Jeong CS]] | ||
| + | [[Category: Kim MY]] | ||
| + | [[Category: Lee JH]] | ||
Current revision
Crystal structure of extended-spectrum class A beta-lactamase, CESS-1 E166Q acylated by ampicillin
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