9ins: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
==MONOVALENT CATION BINDING IN CUBIC INSULIN CRYSTALS== | |||
=== | <StructureSection load='9ins' size='340' side='right' caption='[[9ins]], [[Resolution|resolution]] 1.70Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[9ins]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9INS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=9INS FirstGlance]. <br> | |||
</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=9ins FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ins OCA], [http://www.rcsb.org/pdb/explore.do?structureId=9ins RCSB], [http://www.ebi.ac.uk/pdbsum/9ins 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/in/9ins_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 == | |||
Two localized monovalent cation binding sites have been identified in cubic insulin from 2.8 A-resolution difference electron density maps comparing crystals in which the Na+ ions have been replaced by Tl+. One cation is buried in a closed cavity between insulin dimers and is stabilized by interaction with protein carbonyl dipoles in two juxtaposed alternate positions related by the crystal dyad. The second cation binding site, which also involves ligation with carbonyl dipoles, is competitively occupied by one position of two alternate His B10 side chain conformations. The cation occupancy in both sites depends on the net charge on the protein which was varied by equilibrating crystals in the pH range 7-10. Detailed structures of the cation binding sites were inferred from the refined 2-A resolution map of the sodium-insulin crystal at pH 9. At pH 9, the localized monovalent cations account for less than one of the three to four positive counterion charges necessary to neutralize the negative charge on each protein molecule. The majority of the monovalent counterions are too mobile to show up in the electron density maps calculated using data only at resolution higher than 10 A. Monovalent cations of ionic radius less than 1.5 A are required for crystal stability. Replacing Na+ with Cs+, Mg++, Ca++ or La+++ disrupts the lattice order, but crystals at pH 9 with 0.1 M Li+, K+, NH4+, Rb+ or Tl+ diffract to at least 2.8 A resolution. | |||
Monovalent cation binding to cubic insulin crystals.,Gursky O, Li Y, Badger J, Caspar DL Biophys J. 1992 Mar;61(3):604-11. PMID:1504238<ref>PMID:1504238</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
| Line 10: | Line 28: | ||
*[[PDB identification code|PDB identification code]] | *[[PDB identification code|PDB identification code]] | ||
*[[User:Eric Martz/Introduction to Structural Bioinformatics I|User:Eric Martz/Introduction to Structural Bioinformatics I]] | *[[User:Eric Martz/Introduction to Structural Bioinformatics I|User:Eric Martz/Introduction to Structural Bioinformatics I]] | ||
*[[User:Eric Martz/Introduction to Structural Bioinformatics I%2C | *[[User:Eric Martz/Introduction to Structural Bioinformatics I%2C 2014|User:Eric Martz/Introduction to Structural Bioinformatics I%2C 2014]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Sus scrofa]] | [[Category: Sus scrofa]] | ||
[[Category: Badger, J | [[Category: Badger, J]] | ||
[[Category: Dodson, G G | [[Category: Dodson, G G]] | ||
[[Category: Hormone]] | [[Category: Hormone]] | ||
Revision as of 11:35, 18 December 2014
MONOVALENT CATION BINDING IN CUBIC INSULIN CRYSTALSMONOVALENT CATION BINDING IN CUBIC INSULIN CRYSTALS
Structural highlights
Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedTwo localized monovalent cation binding sites have been identified in cubic insulin from 2.8 A-resolution difference electron density maps comparing crystals in which the Na+ ions have been replaced by Tl+. One cation is buried in a closed cavity between insulin dimers and is stabilized by interaction with protein carbonyl dipoles in two juxtaposed alternate positions related by the crystal dyad. The second cation binding site, which also involves ligation with carbonyl dipoles, is competitively occupied by one position of two alternate His B10 side chain conformations. The cation occupancy in both sites depends on the net charge on the protein which was varied by equilibrating crystals in the pH range 7-10. Detailed structures of the cation binding sites were inferred from the refined 2-A resolution map of the sodium-insulin crystal at pH 9. At pH 9, the localized monovalent cations account for less than one of the three to four positive counterion charges necessary to neutralize the negative charge on each protein molecule. The majority of the monovalent counterions are too mobile to show up in the electron density maps calculated using data only at resolution higher than 10 A. Monovalent cations of ionic radius less than 1.5 A are required for crystal stability. Replacing Na+ with Cs+, Mg++, Ca++ or La+++ disrupts the lattice order, but crystals at pH 9 with 0.1 M Li+, K+, NH4+, Rb+ or Tl+ diffract to at least 2.8 A resolution. Monovalent cation binding to cubic insulin crystals.,Gursky O, Li Y, Badger J, Caspar DL Biophys J. 1992 Mar;61(3):604-11. PMID:1504238[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also
References |
| ||||||||||||||