View source for 1zdb


==PHAGE-SELECTED MINI PROTEIN A DOMAIN, Z38, NMR, MINIMIZED MEAN STRUCTURE==
<StructureSection load='1zdb' size='340' side='right'caption='[[1zdb]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1zdb]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZDB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1ZDB FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=1zdb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1zdb OCA], [https://pdbe.org/1zdb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1zdb RCSB], [https://www.ebi.ac.uk/pdbsum/1zdb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1zdb ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
The affinity between molecules depends both on the nature and presentation of the contacts. Here, we observe coupling of functional and structural elements when a protein binding domain is evolved to a smaller functional mimic. Previously, a 38-residue form of the 59-residue B-domain of protein A, termed Z38, was selected by phage display. Z38 contains 13 mutations and binds IgG only 10-fold weaker than the native B-domain. We present the solution structure of Z38 and show that it adopts a tertiary structure remarkably similar to that observed for the first two helices of B-domain in the B-domain/Fc complex [Deisenhofer, J. (1981) Biochemistry 20, 2361-2370], although it is significantly less stable. Based on this structure, we have improved on Z38 by designing a 34-residue disulfide-bonded variant (Z34C) that has dramatically enhanced stability and binds IgG with 9-fold higher affinity. The improved stability of Z34C led to NMR spectra with much greater chemical shift dispersion, resulting in a more precisely determined structure. Z34C, like Z38, has a structure virtually identical to the equivalent region from native protein A domains. The well-defined hydrophobic core of Z34C reveals key structural features that have evolved in this small, functional domain. Thus, the stabilized two-helix peptide, about half the size and having one-third of the remaining residues altered, accurately mimics both the structure and function of the native domain.

Structural mimicry of a native protein by a minimized binding domain.,Starovasnik MA, Braisted AC, Wells JA Proc Natl Acad Sci U S A. 1997 Sep 16;94(19):10080-5. PMID:9294166<ref>PMID:9294166</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Starovasnik MA]]