1gka
From Proteopedia
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| - | [[Image:1gka.gif|left|200px]]<br /><applet load="1gka" size=" | + | [[Image:1gka.gif|left|200px]]<br /><applet load="1gka" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1gka, resolution 3.23Å" /> | caption="1gka, resolution 3.23Å" /> | ||
'''THE MOLECULAR BASIS OF THE COLORATION MECHANISM IN LOBSTER SHELL. BETA-CRUSTACYANIN AT 3.2 A RESOLUTION'''<br /> | '''THE MOLECULAR BASIS OF THE COLORATION MECHANISM IN LOBSTER SHELL. BETA-CRUSTACYANIN AT 3.2 A RESOLUTION'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1GKA is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homarus_gammarus Homarus gammarus] with AXT, D12, TRS and EPE as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Site: <scene name='pdbsite=AX1:Trs Binding Site For Chain B'>AX1</scene>. Full crystallographic information is available from [http:// | + | 1GKA is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homarus_gammarus Homarus gammarus] with <scene name='pdbligand=AXT:'>AXT</scene>, <scene name='pdbligand=D12:'>D12</scene>, <scene name='pdbligand=TRS:'>TRS</scene> and <scene name='pdbligand=EPE:'>EPE</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Site: <scene name='pdbsite=AX1:Trs+Binding+Site+For+Chain+B'>AX1</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GKA OCA]. |
==Reference== | ==Reference== | ||
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[[Category: lobster]] | [[Category: lobster]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb 3 09:40:38 2008'' |
Revision as of 07:40, 3 February 2008
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THE MOLECULAR BASIS OF THE COLORATION MECHANISM IN LOBSTER SHELL. BETA-CRUSTACYANIN AT 3.2 A RESOLUTION
Overview
The binding of the carotenoid astaxanthin (AXT) in the protein, multimacromolecular complex crustacyanin (CR) is responsible for the blue, coloration of lobster shell. The structural basis of the bathochromic, shift mechanism has long been elusive. A change in color occurs from the, orange red of the unbound dilute AXT (lambda(max) 472 nm in hexane), the, well-known color of cooked lobster, to slate blue in the protein-bound, live lobster state (lambda(max) 632 nm in CR). Intriguingly, extracted CR, becomes red on dehydration and on rehydration goes back to blue. Recently, the innovative use of softer x-rays and xenon derivatization yielded the, three-dimensional structure of the A(1) apoprotein subunit of CR, confirming it as a member of the lipocalin superfamily. That work provided, the molecular replacement search model for a crystal form of the beta-CR, holo complex, that is an A(1) with A(3) subunit assembly including two, bound AXT molecules. We have thereby determined the structure of the A(3), molecule de novo. Lobster has clearly evolved an intricate structural, mechanism for the coloration of its shell using AXT and a bathochromic, shift. Blue/purple AXT proteins are ubiquitous among invertebrate marine, animals, particularly the Crustacea. The three-dimensional structure of, beta-CR has identified the protein contacts and structural alterations, needed for the AXT color regulation mechanism.
About this Structure
1GKA is a Protein complex structure of sequences from Homarus gammarus with , , and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
The molecular basis of the coloration mechanism in lobster shell: beta-crustacyanin at 3.2-A resolution., Cianci M, Rizkallah PJ, Olczak A, Raftery J, Chayen NE, Zagalsky PF, Helliwell JR, Proc Natl Acad Sci U S A. 2002 Jul 23;99(15):9795-800. Epub 2002 Jul 15. PMID:12119396
Page seeded by OCA on Sun Feb 3 09:40:38 2008
Categories: Homarus gammarus | Protein complex | Chayen, N.E. | Cianci, M. | Helliwell, J.R. | Olczak, A. | Raftery, J. | Rizkallah, P.J. | Zagalsky, P.F. | AXT | D12 | EPE | TRS | Astaxanthin | Bathochromic | Coloration | Crustacyanin | Lipocalin | Lobster
