1ptk: Difference between revisions
No edit summary |
No edit summary |
||
| (14 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
==STUDIES ON THE INHIBITORY ACTION OF MERCURY UPON PROTEINASE K== | |||
<StructureSection load='1ptk' size='340' side='right'caption='[[1ptk]], [[Resolution|resolution]] 2.40Å' scene=''> | |||
| | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1ptk]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Parengyodontium_album Parengyodontium album]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PTK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1PTK 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]] 2.4Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</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=1ptk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ptk OCA], [https://pdbe.org/1ptk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ptk RCSB], [https://www.ebi.ac.uk/pdbsum/1ptk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ptk ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/PRTK_PARAQ PRTK_PARAQ] Hydrolyzes keratin at aromatic and hydrophobic residues. | |||
== 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/pt/1ptk_consurf.spt"</scriptWhenChecked> | ||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=1ptk ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
In proteinase K, Cys73 is located "below" the imidazole of the active site His69. In a 2.4-A resolution x-ray crystal structure of the complex formed between the enzyme and HgAc2, two Hg(II) positions are found: a fully occupied site, covalently bound to Cys73 (S gamma), which disrupts the catalytic triad (Asp39-His69-Ser224), and a 2-fold disordered (25 and 35% occupancy), noncovalent complexation to His72, Cys73, and Thr76 of lower affinity. The enzyme is inhibited noncompetitively at low concentrations and competitively above stoichiometric concentrations of Hg(II), but it retains 7% residual activity. This can be rationalized if the molecule is flexible enough to permit transient formation of the catalytic triad. Except for the active site, only minor structural changes are observed upon binding of Hg(II), but the thermal stability is reduced by 4 degrees C. | In proteinase K, Cys73 is located "below" the imidazole of the active site His69. In a 2.4-A resolution x-ray crystal structure of the complex formed between the enzyme and HgAc2, two Hg(II) positions are found: a fully occupied site, covalently bound to Cys73 (S gamma), which disrupts the catalytic triad (Asp39-His69-Ser224), and a 2-fold disordered (25 and 35% occupancy), noncovalent complexation to His72, Cys73, and Thr76 of lower affinity. The enzyme is inhibited noncompetitively at low concentrations and competitively above stoichiometric concentrations of Hg(II), but it retains 7% residual activity. This can be rationalized if the molecule is flexible enough to permit transient formation of the catalytic triad. Except for the active site, only minor structural changes are observed upon binding of Hg(II), but the thermal stability is reduced by 4 degrees C. | ||
Studies on the inhibitory action of mercury upon proteinase K.,Muller A, Saenger W J Biol Chem. 1993 Dec 15;268(35):26150-4. PMID:8253733<ref>PMID:8253733</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1ptk" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Proteinase 3D structures|Proteinase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Parengyodontium album]] | |||
[[Category: Mueller A]] | |||
[[Category: Saenger W]] | |||