1f54: Difference between revisions
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|RELATEDENTRY=[[1f55|1F55]] | |||
|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1f54 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1f54 OCA], [http://www.ebi.ac.uk/pdbsum/1f54 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1f54 RCSB]</span> | |||
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[[Category: helix-loop-helix]] | [[Category: helix-loop-helix]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 20:16:03 2008'' | ||
Revision as of 20:16, 30 March 2008
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| Related: | 1F55
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SOLUTION STRUCTURE OF THE APO N-TERMINAL DOMAIN OF YEAST CALMODULIN
OverviewOverview
We have determined solution structures of the N-terminal half domain (N-domain) of yeast calmodulin (YCM0-N, residues 1-77) in the apo and Ca(2+)-saturated forms by NMR spectroscopy. The Ca(2+)-binding sites of YCM0-N consist of a pair of helix-loop-helix motifs (EF-hands), in which the loops are linked by a short beta-sheet. The binding of two Ca(2+) causes large rearrangement of the four alpha-helices and exposes the hydrophobic surface as observed for vertebrate calmodulin (CaM). Within the observed overall conformational similarity in the peptide backbone, several significant conformational differences were observed between the two proteins, which originated from the 38% disagreement in amino acid sequences. The beta-sheet in apo YCM0-N is strongly twisted compared with that in the N-domain of CaM, while it turns to the normal more stable conformation on Ca(2+) binding. YCM0-N shows higher cooperativity in Ca(2+) binding than the N-domain of CaM, and the observed conformational change of the beta-sheet is a possible cause of the highly cooperative Ca(2+) binding. The hydrophobic surface on Ca(2+)-saturated YCM0-N appears less flexible due to the replacements of Met51, Met71, and Val55 in the hydrophobic surface of CaM with Leu51, Leu71, and Ile55, which is thought to be one of reasons for the poor activation of target enzymes by yeast CaM.
About this StructureAbout this Structure
1F54 is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
ReferenceReference
Solution structures of the N-terminal domain of yeast calmodulin: Ca2+-dependent conformational change and its functional implication., Ishida H, Takahashi K, Nakashima K, Kumaki Y, Nakata M, Hikichi K, Yazawa M, Biochemistry. 2000 Nov 14;39(45):13660-8. PMID:11076504
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