1qx2

<StructureSection load='1qx2' size='340' side='right' caption='[[1qx2]], [[Resolution|resolution]] 1.44&Aring;' scene=''>

<table><tr><td colspan='2'>[[1qx2]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Bovin Bovin]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QX2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1QX2 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>

<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=FME:N-FORMYLMETHIONINE'>FME</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CALB3 OR S100D ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9913 BOVIN])</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=1qx2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qx2 OCA], [http://pdbe.org/1qx2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1qx2 RCSB], [http://www.ebi.ac.uk/pdbsum/1qx2 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1qx2 ProSAT]</span></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

The extent of conformational change that calcium binding induces in EF-hand proteins is a key biochemical property specifying Ca(2+) sensor versus signal modulator function. To understand how differences in amino acid sequence lead to differences in the response to Ca(2+) binding, comparative analyses of sequence and structures, combined with model building, were used to develop hypotheses about which amino acid residues control Ca(2+)-induced conformational changes. These results were used to generate a first design of calbindomodulin (CBM-1), a calbindin D(9k) re-engineered with 15 mutations to respond to Ca(2+) binding with a conformational change similar to that of calmodulin. The gene for CBM-1 was synthesized, and the protein was expressed and purified. Remarkably, this protein did not exhibit any non-native-like molten globule properties despite the large number of mutations and the nonconservative nature of some of them. Ca(2+)-induced changes in CD intensity and in the binding of the hydrophobic probe, ANS, implied that CBM-1 does undergo Ca(2+) sensorlike conformational changes. The X-ray crystal structure of Ca(2+)-CBM-1 determined at 1.44 A resolution reveals the anticipated increase in hydrophobic surface area relative to the wild-type protein. A nascent calmodulin-like hydrophobic docking surface was also found, though it is occluded by the inter-EF-hand loop. The results from this first calbindomodulin design are discussed in terms of progress toward understanding the relationships between amino acid sequence, protein structure, and protein function for EF-hand CaBPs, as well as the additional mutations for the next CBM design.

 

== References ==

[[Category: Bovin]]

[[Category: Bunick, C G]]

[[Category: Bunick, G J]]

[[Category: Chazin, W J]]

[[Category: Mangahas, S]]

[[Category: Mizoue, L S]]

[[Category: Nelson, M R]]

[[Category: Calbindin d9k]]

[[Category: Signaling protein]]