This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1nla
From Proteopedia
(Difference between revisions)
| (11 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| - | [[Image:1nla.jpg|left|200px]] | ||
| - | + | ==Solution Structure of Switch Arc, a Mutant with 3(10) Helices Replacing a Wild-Type Beta-Ribbon== | |
| - | + | <StructureSection load='1nla' size='340' side='right'caption='[[1nla]]' scene=''> | |
| - | + | == Structural highlights == | |
| - | + | <table><tr><td colspan='2'>[[1nla]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Salmonella_virus_P22 Salmonella virus P22]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NLA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NLA 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=1nla FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nla OCA], [https://pdbe.org/1nla PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1nla RCSB], [https://www.ebi.ac.uk/pdbsum/1nla PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1nla ProSAT]</span></td></tr> | |
| - | + | </table> | |
| - | + | == Function == | |
| - | + | [https://www.uniprot.org/uniprot/RARC_BPP22 RARC_BPP22] This protein acts as a transcriptional repressor of its own gene arc and of gene ant. | |
| - | + | <div style="background-color:#fffaf0;"> | |
| - | + | == Publication Abstract from PubMed == | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | == | + | |
Adjacent N11L and L12N mutations in the antiparallel beta-ribbon of Arc repressor result in dramatic changes in local structure in which each beta-strand is replaced by a right-handed helix. The full solution structure of this "switch" Arc mutant shows that irregular 3(10) helices compose the new secondary structure. This structural metamorphosis conserves the number of main-chain and side-chain to main-chain hydrogen bonds and the number of fully buried core residues. Apart from a slight widening of the interhelical angle between alpha-helices A and B and changes in side-chain conformation of a few core residues in Arc, no large-scale structural adjustments in the remainder of the protein are necessary to accommodate the ribbon-to-helix change. Nevertheless, some changes in hydrogen-exchange rates are observed, even in regions that have very similar structures in the two proteins. The surface of switch Arc is packed poorly compared to wild-type, leading to approximately 1000A(2) of additional solvent-accessible surface area, and the N termini of the 3(10) helices make unfavorable head-to-head electrostatic interactions. These structural features account for the positive m value and salt dependence of the ribbon-to-helix transition in Arc-N11L, a variant that can adopt either the mutant or wild-type structures. The tertiary fold is capped in different ways in switch and wild-type Arc, showing how stepwise evolutionary transformations can arise through small changes in amino acid sequence. | Adjacent N11L and L12N mutations in the antiparallel beta-ribbon of Arc repressor result in dramatic changes in local structure in which each beta-strand is replaced by a right-handed helix. The full solution structure of this "switch" Arc mutant shows that irregular 3(10) helices compose the new secondary structure. This structural metamorphosis conserves the number of main-chain and side-chain to main-chain hydrogen bonds and the number of fully buried core residues. Apart from a slight widening of the interhelical angle between alpha-helices A and B and changes in side-chain conformation of a few core residues in Arc, no large-scale structural adjustments in the remainder of the protein are necessary to accommodate the ribbon-to-helix change. Nevertheless, some changes in hydrogen-exchange rates are observed, even in regions that have very similar structures in the two proteins. The surface of switch Arc is packed poorly compared to wild-type, leading to approximately 1000A(2) of additional solvent-accessible surface area, and the N termini of the 3(10) helices make unfavorable head-to-head electrostatic interactions. These structural features account for the positive m value and salt dependence of the ribbon-to-helix transition in Arc-N11L, a variant that can adopt either the mutant or wild-type structures. The tertiary fold is capped in different ways in switch and wild-type Arc, showing how stepwise evolutionary transformations can arise through small changes in amino acid sequence. | ||
| - | + | Solution structure of switch Arc, a mutant with 3(10) helices replacing a wild-type beta-ribbon.,Cordes MH, Walsh NP, McKnight CJ, Sauer RT J Mol Biol. 2003 Feb 21;326(3):899-909. PMID:12581649<ref>PMID:12581649</ref> | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | Solution structure of switch Arc, a mutant with 3(10) helices replacing a wild-type beta-ribbon., Cordes MH, Walsh NP, McKnight CJ, Sauer RT | + | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| + | </div> | ||
| + | <div class="pdbe-citations 1nla" style="background-color:#fffaf0;"></div> | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Salmonella virus P22]] | ||
| + | [[Category: Cordes MH]] | ||
| + | [[Category: McKnight CJ]] | ||
| + | [[Category: Sauer RT]] | ||
| + | [[Category: Walsh NP]] | ||
Current revision
Solution Structure of Switch Arc, a Mutant with 3(10) Helices Replacing a Wild-Type Beta-Ribbon
| |||||||||||
