1mks: Difference between revisions
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==CARBOXYLIC ESTER HYDROLASE, TRIGONAL FORM OF THE TRIPLE MUTANT== | |||
<StructureSection load='1mks' size='340' side='right'caption='[[1mks]], [[Resolution|resolution]] 1.90Å' scene=''> | |||
| | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1mks]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MKS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1MKS 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]] 1.9Å</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></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=1mks FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1mks OCA], [https://pdbe.org/1mks PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1mks RCSB], [https://www.ebi.ac.uk/pdbsum/1mks PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1mks ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/PA21B_BOVIN PA21B_BOVIN] PA2 catalyzes the calcium-dependent hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides. | |||
== 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/mk/1mks_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=1mks ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The aspartate-99 of secreted phospholipase A2 (PLA2) has been proposed to be critical for the catalytic mechanism and interfacial activation of PLA2. Aspartate-99 connects the catalytic machinery (including the catalytic diad, the putative catalytic waters W5 and W6, and the calcium cofactor) to the hydrogen-bonding network. The latter involves Y52, Y73, the structural water, and the N-terminal region putatively required for the interfacial activation. A triple mutant of bovine pancreatic PLA2 with substitutions aspartate plus adjacent tyrosine residues (Y52,73F/D99N) was constructed, its X-ray structure was determined, and kinetic characteristics were analyzed. The kinetic properties of the D99N mutant constructed previously were also further analyzed. The X-ray structure of the Y52,73F/D99N mutant indicated a substantial disruption of the hydrogen-bonding network including the loss of the structural water similar to that seen in the structure of the D99N mutant published previously [Kumar, A., Sekharudu, Y. C., Ramakrishnan, B., Dupureur, C. M., Zhu, H., Tsai, M.-D., & Sundaralingam, M. (1994) Protein Sci. 3, 2082-2088]. Kinetic analysis demonstrated that these mutants possessed considerable catalytic activity with a k(cat) value of about 5% compared to WT. The values of the interfacial Michaelis constant were also little perturbed (ca. 4-fold lower for D99N and marginally higher for Y52,73F/D99N). The results taken together suggest that the hydrogen-bonding network is not critically important for interfacial activation. Instead, it is the chemical step that is perturbed, though only modestly, in the mutants. | |||
Phospholipase A2 engineering. Structural and functional roles of the highly conserved active site residue aspartate-99.,Sekar K, Yu BZ, Rogers J, Lutton J, Liu X, Chen X, Tsai MD, Jain MK, Sundaralingam M Biochemistry. 1997 Mar 18;36(11):3104-14. PMID:9115986<ref>PMID:9115986</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1mks" style="background-color:#fffaf0;"></div> | |||
== | ==See Also== | ||
*[[Phospholipase A2 3D structures|Phospholipase A2 3D structures]] | |||
== References == | |||
== | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Bos taurus]] | [[Category: Bos taurus]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Sundaralingam M]] | |||
[[Category: Sundaralingam | |||