2anp
From Proteopedia
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- | [[ | + | ==Functional Glutamate 151 to Histidine mutant of the aminopeptidase from Aeromonas Proteolytica.== |
+ | <StructureSection load='2anp' size='340' side='right' caption='[[2anp]], [[Resolution|resolution]] 1.90Å' scene=''> | ||
+ | == Structural highlights == | ||
+ | <table><tr><td colspan='2'>[[2anp]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Vibrio_proteolyticus Vibrio proteolyticus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ANP OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2ANP FirstGlance]. <br> | ||
+ | </td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene><br> | ||
+ | <tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1amp|1amp]], [[1lok|1lok]], [[1cp6|1cp6]], [[1txr|1txr]]</td></tr> | ||
+ | <tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Bacterial_leucyl_aminopeptidase Bacterial leucyl aminopeptidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.11.10 3.4.11.10] </span></td></tr> | ||
+ | <tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2anp FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2anp OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2anp RCSB], [http://www.ebi.ac.uk/pdbsum/2anp PDBsum]</span></td></tr> | ||
+ | <table> | ||
+ | == 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/an/2anp_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/chain_selection.php?pdb_ID=2ata ConSurf]. | ||
+ | <div style="clear:both"></div> | ||
+ | <div style="background-color:#fffaf0;"> | ||
+ | == Publication Abstract from PubMed == | ||
+ | Glutamate151 (E151) has been shown to be catalytically essential for the aminopeptidase from Vibrio proteolyticus (AAP). E151 acts as the general acid/base during the catalytic mechanism of peptide hydrolysis. However, a glutamate residue is not the only residue capable of functioning as a general acid/base during catalysis for dinuclear metallohydrolases. Recent crystallographic characterization of the D-aminopeptidase from Bacillus subtilis (DppA) revealed a histidine residue that resides in an identical position to E151 in AAP. Because the active-site ligands for DppA and AAP are identical, AAP has been used as a model enzyme to understand the mechanistic role of H115 in DppA. Substitution of E151 with histidine resulted in an active AAP enzyme exhibiting a kcat value of 2.0 min(-1), which is over 2000 times slower than r AAP (4380 min(-1)). ITC experiments revealed that ZnII binds 330 and 3 times more weakly to E151H-AAP compared to r-AAP. UV-vis and EPR spectra of CoII-loaded E151H-AAP indicated that the first metal ion resides in a hexacoordinate/pentacoordinate equilibrium environment, whereas the second metal ion is six-coordinate. pH dependence of the kinetic parameters kcat and K(m) for the hydrolysis of L-leucine p-nitroanilide (L-pNA) revealed a change in an ionization constant in the enzyme-substrate complex from 5.3 in r-AAP to 6.4 in E151H-AAP, consistent with E151 in AAP being the active-site general acid/base. Proton inventory studies at pH 8.50 indicate the transfer of one proton in the rate-limiting step of the reaction. Moreover, the X-ray crystal structure of [ZnZn(E151H-AAP)] has been solved to 1.9 A resolution, and alteration of E151 to histidine does not introduce any major conformational changes to the overall protein structure or the dinuclear ZnII active site. Therefore, a histidine residue can function as the general acid/base in hydrolysis reactions of peptides and, through analogy of the role of E151 in AAP, H115 in DppA likely shuttles a proton to the leaving group of the substrate. | ||
- | + | Kinetic, spectroscopic, and X-ray crystallographic characterization of the functional E151H aminopeptidase from Aeromonas proteolytica.,Bzymek KP, Moulin A, Swierczek SI, Ringe D, Petsko GA, Bennett B, Holz RC Biochemistry. 2005 Sep 13;44(36):12030-40. PMID:16142900<ref>PMID:16142900</ref> | |
- | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
- | + | </div> | |
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==See Also== | ==See Also== | ||
*[[Aminopeptidase|Aminopeptidase]] | *[[Aminopeptidase|Aminopeptidase]] | ||
- | + | == References == | |
- | == | + | <references/> |
- | < | + | __TOC__ |
+ | </StructureSection> | ||
[[Category: Bacterial leucyl aminopeptidase]] | [[Category: Bacterial leucyl aminopeptidase]] | ||
[[Category: Vibrio proteolyticus]] | [[Category: Vibrio proteolyticus]] |
Revision as of 05:23, 29 September 2014
Functional Glutamate 151 to Histidine mutant of the aminopeptidase from Aeromonas Proteolytica.
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