2aio: Difference between revisions

<StructureSection load='2aio' size='340' side='right'caption='[[2aio]], [[Resolution|resolution]] 1.70&Aring;' scene=''>

== Structural highlights ==

<table><tr><td colspan='2'>[[2aio]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Stenotrophomonas_maltophilia Stenotrophomonas maltophilia]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AIO OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2AIO 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]] 1.7&#8491;</td></tr>

<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MX1:(2R)-2-((R)-CARBOXY{[CARBOXY(4-HYDROXYPHENYL)ACETYL]AMINO}METHOXYMETHYL)-5-METHYLENE-5,6-DIHYDRO-2H-1,3-OXAZINE-4-CARBOXYLIC+ACID'>MX1</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=2aio FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aio OCA], [https://pdbe.org/2aio PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2aio RCSB], [https://www.ebi.ac.uk/pdbsum/2aio PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2aio ProSAT]</span></td></tr>

== Function ==

[https://www.uniprot.org/uniprot/BLA1_STEMA BLA1_STEMA] Has a high activity against imipenem.

== Evolutionary Conservation ==

[[Image:Consurf_key_small.gif|200px|right]]

    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ai/2aio_consurf.spt"</scriptWhenChecked>

</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2aio ConSurf].

<div style="clear:both"></div>

Metallo-beta-lactamases are zinc-dependent enzymes responsible for resistance to beta-lactam antibiotics in a variety of host bacteria, usually Gram-negative species that act as opportunist pathogens. They hydrolyze all classes of beta-lactam antibiotics, including carbapenems, and escape the action of available beta-lactamase inhibitors. Efforts to develop effective inhibitors have been hampered by the lack of structural information regarding how these enzymes recognize and turn over beta-lactam substrates. We report here the crystal structure of the Stenotrophomonas maltophilia L1 enzyme in complex with the hydrolysis product of the 7alpha-methoxyoxacephem, moxalactam. The on-enzyme complex is a 3'-exo-methylene species generated by elimination of the 1-methyltetrazolyl-5-thiolate anion from the 3'-methyl group. Moxalactam binding to L1 involves direct interaction of the two active site zinc ions with the beta-lactam amide and C4 carboxylate, groups that are common to all beta-lactam substrates. The 7beta-[(4-hydroxyphenyl)malonyl]-amino substituent makes limited hydrophobic and hydrogen bonding contacts with the active site groove. The mode of binding provides strong evidence that a water molecule situated between the two metal ions is the most likely nucleophile in the hydrolytic reaction. These data suggest a reaction mechanism for metallo-beta-lactamases in which both metal ions contribute to catalysis by activating the bridging water/hydroxide nucleophile, polarizing the substrate amide bond for attack and stabilizing anionic nitrogen intermediates. The structure illustrates how a binuclear zinc site confers upon metallo-beta-lactamases the ability both to recognize and efficiently hydrolyze a wide variety of beta-lactam substrates.

Antibiotic recognition by binuclear metallo-beta-lactamases revealed by X-ray crystallography.,Spencer J, Read J, Sessions RB, Howell S, Blackburn GM, Gamblin SJ J Am Chem Soc. 2005 Oct 19;127(41):14439-44. PMID:16218639<ref>PMID:16218639</ref>

==See Also==

*[[Beta-lactamase 3D structures|Beta-lactamase 3D structures]]

== References ==

<references/>

</StructureSection>

[[Category: Large Structures]]

[[Category: Blackburn GM]]

[[Category: Gamblin SJ]]

[[Category: Howell S]]

[[Category: Read J]]

[[Category: Sessions RB]]

[[Category: Spencer J]]