View source for 1k53


==Monomeric Protein L B1 Domain with a G15A Mutation==
<StructureSection load='1k53' size='340' side='right'caption='[[1k53]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1k53]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Finegoldia_magna_ATCC_29328 Finegoldia magna ATCC 29328]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1K53 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1K53 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</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=1k53 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1k53 OCA], [https://pdbe.org/1k53 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1k53 RCSB], [https://www.ebi.ac.uk/pdbsum/1k53 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1k53 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q51912_FINMA Q51912_FINMA] 
== 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/k5/1k53_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/main_output.php?pdb_ID=1k53 ConSurf].
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== Publication Abstract from PubMed ==
BACKGROUND: Thermodynamic and kinetic studies of the Protein L B1 domain (Ppl) suggest a folding pathway in which, during the folding transition, the first beta hairpin is formed while the second beta hairpin and the alpha helix are largely unstructured. The same mutations in the two beta turns have opposite effects on the folding and unfolding rates. Three of the four residues composing the second beta turn in Ppl have consecutive positive phi angles, indicating strain in the second beta turn. RESULTS: We have determined the crystal structures of the beta turn mutants G55A, K54G, and G15A, as well as a core mutant, V49A, in order to investigate how backbone strain affects the overall structure of Ppl. Perturbation of the hydrophobic interactions at the closed interface by the V49A mutation triggered the domain swapping of the C-terminal beta strand that relieved the strain in the second beta turn. Interestingly, the asymmetric unit of V49A contains two monomers and one domain-swapped dimer. The G55A mutation escalated the strain in the second beta turn, and this increased strain shifted the equilibrium toward the domain-swapped dimer. The K54G structure revealed that the increased stability is due to the reduction of strain in the second beta turn, while the G15A structure showed that increased strain alone is insufficient to trigger domain swapping. CONCLUSIONS: Domain swapping in Ppl is determined by the balance of two opposing components of the free energy. One is the strain in the second beta turn that favors the dimer, and the other is the entropic cost of dimer formation that favors the monomer. A single-site mutation can disrupt this balance and trigger domain swapping.

Single-site mutations induce 3D domain swapping in the B1 domain of protein L from Peptostreptococcus magnus.,O'Neill JW, Kim DE, Johnsen K, Baker D, Zhang KY Structure. 2001 Nov;9(11):1017-27. PMID:11709166<ref>PMID:11709166</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1k53" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Finegoldia magna ATCC 29328]]
[[Category: Large Structures]]
[[Category: Baker D]]
[[Category: Johnsen K]]
[[Category: Kim DE]]
[[Category: O'Neill JW]]
[[Category: Zhang KYJ]]