View source for 2wik

==NONAGED FORM OF HUMAN BUTYRYLCHOLINESTERASE INHIBITED BY TABUN ANALOGUE TA6==
<StructureSection load='2wik' size='340' side='right' caption='[[2wik]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2wik]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2WIK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2WIK FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=TC5:ETHYL+HYDROGEN+PROPYLAMIDOPHOSPHATE'>TC5</scene>, <scene name='pdbligand=FUL:BETA-L-FUCOSE'>FUL</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1ehq|1ehq]], [[1p0q|1p0q]], [[2j4c|2j4c]], [[1kcj|1kcj]], [[1p0p|1p0p]], [[1xlu|1xlu]], [[1xlv|1xlv]], [[1eho|1eho]], [[2wif|2wif]], [[1p0m|1p0m]], [[1xlw|1xlw]], [[1p0i|1p0i]], [[2wid|2wid]], [[2wij|2wij]], [[2wig|2wig]]</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Cholinesterase Cholinesterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.8 3.1.1.8] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2wik FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2wik OCA], [http://pdbe.org/2wik PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2wik RCSB], [http://www.ebi.ac.uk/pdbsum/2wik PDBsum]</span></td></tr>
</table>
== Disease ==
[[http://www.uniprot.org/uniprot/CHLE_HUMAN CHLE_HUMAN]] Defects in BCHE are the cause of butyrylcholinesterase deficiency (BChE deficiency) [MIM:[http://omim.org/entry/177400 177400]]. BChE deficiency is a metabolic disorder characterized by prolonged apnoea after the use of certain anesthetic drugs, including the muscle relaxants succinylcholine or mivacurium and other ester local anesthetics. The duration of the prolonged apnoea varies significantly depending on the extent of the enzyme deficiency. BChE deficiency is a multifactorial disorder. The hereditary condition is transmitted as an autosomal recessive trait. 
== Function ==
[[http://www.uniprot.org/uniprot/CHLE_HUMAN CHLE_HUMAN]] Esterase with broad substrate specificity. Contributes to the inactivation of the neurotransmitter acetylcholine. Can degrade neurotoxic organophosphate esters.<ref>PMID:19542320</ref> <ref>PMID:19452557</ref>  
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/wi/2wik_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</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=2wik ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
hBChE [human BChE (butyrylcholinesterase)] naturally scavenges OPs (organophosphates). This bioscavenger is currently in Clinical Phase I for pretreatment of OP intoxication. Phosphylated ChEs (cholinesterases) can undergo a spontaneous time-dependent process called 'aging' during which the conjugate is dealkylated, leading to creation of an enzyme that cannot be reactivated. hBChE inhibited by phosphoramidates such as tabun displays a peculiar resistance to oxime-mediated reactivation. We investigated the basis of oxime resistance of phosphoramidyl-BChE conjugates by determining the kinetics of inhibition, reactivation (obidoxime {1,1'-(oxybis-methylene) bis[4-(hydroxyimino) methyl] pyridinium dichloride}, TMB-4 [1,3-trimethylene-bis(4-hydroxyiminomethylpyridinium) dibromide], HLo 7 {1-[[[4-(aminocarbonyl) pyridinio]methoxy]methyl]-2,4-bis-[(hydroxyimino)methyl] pyridinium dimethanesulfonate)}, HI-6 {1-[[[4-(aminocarbonyl) pyridinio] methoxy] methyl]-2-[(hydroxyimino)methyl]pyridinium dichloride monohydrate} and aging, and the crystal structures of hBChE inhibited by different N-monoalkyl and N,N-dialkyl tabun analogues. The refined structures of aged hBChE conjugates show that aging proceeds through O-dealkylation of the P(R) enantiomer of N,N-diethyl and N-propyl analogues, with subsequent formation of a salt bridge preventing reactivation, similarly to a previous observation made on tabun-ChE conjugates. Interestingly, the N-methyl analogue projects its amino group towards the choline-binding pocket, so that aging proceeds through deamination. This orientation results from a preference of hBChE's acyl-binding pocket for larger than 2-atoms linear substituents. The correlation between the inhibitory potency and the N-monoalkyl chain length is related to increasingly optimized interactions with the acyl-binding pocket as shown by the X-ray structures. These kinetics and X-ray data lead to a structure-activity relationship that highlights steric and electronic effects of the amino substituent of phosphoramidate. This study provides the structural basis to design new oximes capable of reactivating phosphoramidyl-hBChE conjugates after intoxication, notably when hBChE is used as pretreatment, or to design BChE-based catalytic bioscavengers.

Structure-activity analysis of aging and reactivation of human butyrylcholinesterase inhibited by analogues of tabun.,Carletti E, Aurbek N, Gillon E, Loiodice M, Nicolet Y, Fontecilla-Camps JC, Masson P, Thiermann H, Nachon F, Worek F Biochem J. 2009 Jun 12;421(1):97-106. PMID:19368529<ref>PMID:19368529</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2wik" style="background-color:#fffaf0;"></div>

==See Also==
*[[Butyrylcholinesterase|Butyrylcholinesterase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Cholinesterase]]
[[Category: Human]]
[[Category: Aurbek, N]]
[[Category: Carletti, E]]
[[Category: Fontecilla, J]]
[[Category: Gillon, E]]
[[Category: Loiodice, M]]
[[Category: Masson, P]]
[[Category: Nachon, F]]
[[Category: Nicolet, Y]]
[[Category: Thiermann, H]]
[[Category: Worek, F]]
[[Category: Aging]]
[[Category: Disease mutation]]
[[Category: Glycoprotein]]
[[Category: Hydrolase]]
[[Category: Inhibition]]
[[Category: Serine esterase]]