1cqk

<table><tr><td colspan='2'>[[1cqk]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Lk3_transgenic_mice Lk3 transgenic mice]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CQK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1CQK FirstGlance]. <br>

</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=1cqk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cqk OCA], [https://pdbe.org/1cqk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1cqk RCSB], [https://www.ebi.ac.uk/pdbsum/1cqk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1cqk ProSAT]</span></td></tr>

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== Publication Abstract from PubMed ==

The simplest naturally occurring model system for studying immunoglobulin folding and assembly is the non-covalent homodimer formed by the C-terminal domains (CH3) of the heavy chains of IgG. Here, we describe the structure of recombinant CH3 dimer as determined by X-ray crystallography and an analysis of the folding pathway of this protein.Under conditions where prolyl isomerization does not contribute to the folding kinetics, formation of the beta-sandwich structure is the rate-limiting step. beta-Sheet formation of CH3 is a slow process, even compared to other antibody domains, while the subsequent association of the folded monomers is fast. After long-time denaturation, the majority of the unfolded CH3 molecules reaches the native state in two serial reactions, involving the re-isomerization of the Pro35-peptide bond to the cis configuration. The species with the wrong isomer accumulate as a monomeric intermediate. Importantly, the isomerization to the correct cis configuration is the prerequisite for dimerization of the CH3 domain. In contrast, in the Fab fragment of the same antibody, prolyl isomerization occurs after dimerization demonstrating that within one protein, comprised of highly homologous domains, both the kinetics of beta-sandwich formation and the stage at which prolyl isomerization occurs during the folding process can be completely different.

Folding and association of the antibody domain CH3: prolyl isomerization preceeds dimerization.,Thies MJ, Mayer J, Augustine JG, Frederick CA, Lilie H, Buchner J J Mol Biol. 1999 Oct 15;293(1):67-79. PMID:10512716<ref>PMID:10512716</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Lk3 transgenic mice]]

[[Category: Augustine, J G]]

[[Category: Buchner, J]]

[[Category: Frederick, C A]]

[[Category: Lilie, H]]

[[Category: Mayer, J]]

[[Category: Thies, M J]]

[[Category: Immunoglobulin]]