2v1v: Difference between revisions
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== | ==3D STRUCTURE OF THE M8L MUTANT OF SQUASH TRYPSIN INHIBITOR CMTI-I== | ||
Protein molecules can accommodate a large number of mutations without | <StructureSection load='2v1v' size='340' side='right'caption='[[2v1v]]' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2v1v]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Cucurbita_maxima Cucurbita maxima]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1bxj 1bxj]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2V1V OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2V1V 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=2v1v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2v1v OCA], [https://pdbe.org/2v1v PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2v1v RCSB], [https://www.ebi.ac.uk/pdbsum/2v1v PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2v1v ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/ITR1_CUCMA ITR1_CUCMA] Inhibits trypsin. | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Protein molecules can accommodate a large number of mutations without noticeable effects on their stability and folding kinetics. On the other hand, some mutations can have quite strong effects on protein conformational properties. Such mutations either destabilize secondary structures, e.g., alpha-helices, are incompatible with close packing of protein hydrophobic cores, or lead to disruption of some specific interactions such as disulfide cross links, salt bridges, hydrogen bonds, or aromatic-aromatic contacts. The Met8 --> Leu mutation in CMTI-I results in significant destabilization of the protein structure. This effect could hardly be expected since the mutation is highly conservative, and the side chain of residue 8 is situated on the protein surface. We show that the protein destabilization is caused by rearrangement of a hydrophobic cluster formed by side chains of residues 8, Ile6, and Leu17 that leads to partial breaking of a hydrogen bond formed by the amide group of Leu17 with water and to a reduction of a hydrophobic surface buried within the cluster. The mutation perturbs also the protein folding. In aerobic conditions the reduced wild-type protein folds effectively into its native structure, whereas more then 75% of the mutant molecules are trapped in various misfolded species. The main conclusion of this work is that conservative mutations of hydrophobic residues can destabilize a protein structure even if these residues are situated on the protein surface and partially accessible to water. Structural rearrangement of small hydrophobic clusters formed by such residues can lead to local changes in protein hydration, and consequently, can affect considerably protein stability and folding process. | |||
Conservative mutation Met8 --> Leu affects the folding process and structural stability of squash trypsin inhibitor CMTI-I.,Zhukov I, Jaroszewski L, Bierzynski A Protein Sci. 2000 Feb;9(2):273-9. PMID:10716179<ref>PMID:10716179</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2v1v" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Trypsin inhibitor 3D structures|Trypsin inhibitor 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Cucurbita maxima]] | |||
[[Category: Large Structures]] | |||
[[Category: Bierzynski A]] | |||
[[Category: Bolewska K]] | |||
[[Category: Sledz P]] | |||
[[Category: Zhukov I]] | |||
Latest revision as of 16:11, 26 July 2023
3D STRUCTURE OF THE M8L MUTANT OF SQUASH TRYPSIN INHIBITOR CMTI-I3D STRUCTURE OF THE M8L MUTANT OF SQUASH TRYPSIN INHIBITOR CMTI-I
Structural highlights
FunctionITR1_CUCMA Inhibits trypsin. Publication Abstract from PubMedProtein molecules can accommodate a large number of mutations without noticeable effects on their stability and folding kinetics. On the other hand, some mutations can have quite strong effects on protein conformational properties. Such mutations either destabilize secondary structures, e.g., alpha-helices, are incompatible with close packing of protein hydrophobic cores, or lead to disruption of some specific interactions such as disulfide cross links, salt bridges, hydrogen bonds, or aromatic-aromatic contacts. The Met8 --> Leu mutation in CMTI-I results in significant destabilization of the protein structure. This effect could hardly be expected since the mutation is highly conservative, and the side chain of residue 8 is situated on the protein surface. We show that the protein destabilization is caused by rearrangement of a hydrophobic cluster formed by side chains of residues 8, Ile6, and Leu17 that leads to partial breaking of a hydrogen bond formed by the amide group of Leu17 with water and to a reduction of a hydrophobic surface buried within the cluster. The mutation perturbs also the protein folding. In aerobic conditions the reduced wild-type protein folds effectively into its native structure, whereas more then 75% of the mutant molecules are trapped in various misfolded species. The main conclusion of this work is that conservative mutations of hydrophobic residues can destabilize a protein structure even if these residues are situated on the protein surface and partially accessible to water. Structural rearrangement of small hydrophobic clusters formed by such residues can lead to local changes in protein hydration, and consequently, can affect considerably protein stability and folding process. Conservative mutation Met8 --> Leu affects the folding process and structural stability of squash trypsin inhibitor CMTI-I.,Zhukov I, Jaroszewski L, Bierzynski A Protein Sci. 2000 Feb;9(2):273-9. PMID:10716179[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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