From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:1uhh.gif|left|200px]] | + | {{Seed}} |
| | + | [[Image:1uhh.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_1uhh| PDB=1uhh | SCENE= }} | | {{STRUCTURE_1uhh| PDB=1uhh | SCENE= }} |
| | | | |
| - | '''Crystal structure of cp-aequorin'''
| + | ===Crystal structure of cp-aequorin=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | The photoprotein aequorin emits light by an intramolecular reaction in the presence of a trace amount of Ca(2+). Semi-synthetic aequorins, produced by replacing the coelenterazine moiety in aequorin with the analogues of coelenterazine, show widely different sensitivities to Ca(2+). To understand the structural basis of the Ca(2+)-sensitivity, we determined the crystal structures of four semi-synthetic aequorins (cp-, i-, br- and n-aequorins) at resolutions of 1.6-1.8 A. In general, the protein structures of these semi-synthetic aequorins are almost identical to native aequorin. Of the four EF-hand domains in the molecule, EF-hand II does not bind Ca(2+), and the loop of EF-hand IV is clearly deformed. It is most likely that the binding of Ca(2+) with EF-hands I and III triggers luminescence. Although little difference was found in the overall structures of aequorins investigated, some significant differences were found in the interactions between the substituents of coelenterazine moiety and the amino acid residues in the binding pocket. The coelenterazine moieties in i-, br-, and n-aequorins have bulky 2-substitutions, which can interfere with the conformational changes of protein structure that follow the binding of Ca(2+) to aequorin. In cp-aequorin, the cyclopentylmethyl group that substitutes for the original 8-benzyl group does not interact hydrophobically with the protein part, giving the coelenterazine moiety more conformational freedom to promote the light-emitting reaction. The differences of various semi-synthetic aequorins in Ca(2+)-sensitivity and reaction rate are explained by the capability of the involved groups and structures to undergo conformational changes in response to the Ca(2+)-binding. | + | The line below this paragraph, {{ABSTRACT_PUBMED_15632284}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 15632284 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_15632284}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 30: |
Line 34: |
| | [[Category: 4 ef-hand motif]] | | [[Category: 4 ef-hand motif]] |
| | [[Category: Complex]] | | [[Category: Complex]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 11:14:08 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 02:28:36 2008'' |
Revision as of 23:28, 27 July 2008
Template:STRUCTURE 1uhh
Crystal structure of cp-aequorin
Template:ABSTRACT PUBMED 15632284
About this Structure
1UHH is a Single protein structure of sequence from Aequorea victoria. Full crystallographic information is available from OCA.
Reference
The crystal structures of semi-synthetic aequorins., Toma S, Chong KT, Nakagawa A, Teranishi K, Inouye S, Shimomura O, Protein Sci. 2005 Feb;14(2):409-16. Epub 2005 Jan 4. PMID:15632284
Page seeded by OCA on Mon Jul 28 02:28:36 2008
