1dx9
From Proteopedia
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| - | [[Image:1dx9.jpg|left|200px]] | + | [[Image:1dx9.jpg|left|200px]] |
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| - | '''W57A APOFLAVODOXIN FROM ANABAENA''' | + | {{Structure |
| + | |PDB= 1dx9 |SIZE=350|CAPTION= <scene name='initialview01'>1dx9</scene>, resolution 2.05Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=SO4:SULFATE ION'>SO4</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
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| + | '''W57A APOFLAVODOXIN FROM ANABAENA''' | ||
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==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1DX9 is a [ | + | 1DX9 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Anabaena_sp. Anabaena sp.]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DX9 OCA]. |
==Reference== | ==Reference== | ||
| - | Dissecting the energetics of the apoflavodoxin-FMN complex., Lostao A, El Harrous M, Daoudi F, Romero A, Parody-Morreale A, Sancho J, J Biol Chem. 2000 Mar 31;275(13):9518-26. PMID:[http:// | + | Dissecting the energetics of the apoflavodoxin-FMN complex., Lostao A, El Harrous M, Daoudi F, Romero A, Parody-Morreale A, Sancho J, J Biol Chem. 2000 Mar 31;275(13):9518-26. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10734100 10734100] |
[[Category: Anabaena sp.]] | [[Category: Anabaena sp.]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: flavoprotein]] | [[Category: flavoprotein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 10:45:53 2008'' |
Revision as of 08:45, 20 March 2008
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| , resolution 2.05Å | |||||||
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| Coordinates: | save as pdb, mmCIF, xml | ||||||
W57A APOFLAVODOXIN FROM ANABAENA
Overview
Many flavoproteins are non-covalent complexes between FMN and an apoprotein. To understand better the stability of flavoproteins, we have studied the energetics of the complex between FMN and the apoflavodoxin from Anabaena PCC 7119 by a combination of site-directed mutagenesis, titration calorimetry, equilibrium binding constant determinations, and x-ray crystallography. Comparison of the strength of the wild type and mutant apoflavodoxin-FMN complexes and that of the complexes between wild type apoflavodoxin and shortened FMN analogues (riboflavin and lumiflavin) allows the dissection of the binding energy into contributions associated with the different parts of the FMN molecule. The estimated contribution of the phosphate is greatest, at 7 kcal mol(-1); that of the isoalloxazine is of around 5-6 kcal mol(-1) (mainly due to interaction with Trp-57 and Tyr-94 in the apoprotein) and the ribityl contributes least: around 1 kcal mol(-1). The stabilization of the complex is both enthalpic and entropic although the enthalpy contribution is dominant. Both the phosphate and the isoalloxazine significantly contribute to the enthalpy of binding. The ionic strength does not have a large effect on the stability of the FMN complex because, although it weakens the phosphate interactions, it strengthens the isoalloxazine-protein hydrophobic interactions. Phosphate up to 100 mM does not affect the strength of the riboflavin complex, which suggests the isoalloxazine and phosphate binding sites may be independent in terms of binding energy. Interestingly, we find crystallographic evidence of flexibility in one of the loops (57-62) involved in isoalloxazine binding.
About this Structure
1DX9 is a Single protein structure of sequence from Anabaena sp.. Full crystallographic information is available from OCA.
Reference
Dissecting the energetics of the apoflavodoxin-FMN complex., Lostao A, El Harrous M, Daoudi F, Romero A, Parody-Morreale A, Sancho J, J Biol Chem. 2000 Mar 31;275(13):9518-26. PMID:10734100
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