2a8g: Difference between revisions
No edit summary |
No edit summary |
||
| Line 4: | Line 4: | ||
|PDB= 2a8g |SIZE=350|CAPTION= <scene name='initialview01'>2a8g</scene>, resolution 1.990Å | |PDB= 2a8g |SIZE=350|CAPTION= <scene name='initialview01'>2a8g</scene>, resolution 1.990Å | ||
|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene> and <scene name='pdbligand=GNG:2 | |LIGAND= <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene> and <scene name='pdbligand=GNG:2'-DEOXY-GUANOSINE'>GNG</scene> | ||
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| Line 30: | Line 30: | ||
[[Category: beta barrel]] | [[Category: beta barrel]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 23 14:35:25 2008'' | ||
Revision as of 12:35, 23 March 2008
| |||||||||||||
| 2a8g, resolution 1.990Å | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ligands: | NAG and GNG | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
Structure of Avidin in complex with the ligand deoxyguanosine
Overview
Oxidative damage of DNA results in the formation of many products, including 8-oxodeoxyguanosine, which has been used as a marker to quantify DNA damage. Earlier studies have demonstrated that avidin, a protein prevalent in egg-white and which has high affinity for the vitamin biotin, binds to 8-oxodeoxyguanosine and related bases. In this study, we have determined crystal structures of avidin in complex with 8-oxodeoxyguanosine and 8-oxodeoxyadenosine. In each case, the base is observed to bind within the biotin-binding site of avidin. However, the mode of association between the bases and the protein varies and, unlike in the avidin:biotin complex, complete ordering of the protein in this region does not accompany binding. Fluorescence studies indicate that in solution the individual bases, and a range of oligonucleotides, bind to avidin with micromolar affinity. Only one of the modes of binding observed is consistent with recognition of oxidised purines when incorporated within a DNA oligomer, and from this structure a model is proposed for the selective binding of avidin to DNA containing oxidatively damaged deoxyguanosine. These studies illustrate the molecular basis by which avidin might act as a marker of DNA damage, although the low levels of binding observed are inconsistent with the recognition of oxidised purines forming a major physiological role for avidin.
About this Structure
2A8G is a Single protein structure of sequence from Gallus gallus. Full crystallographic information is available from OCA.
Reference
Recognition of oxidatively modified bases within the biotin-binding site of avidin., Conners R, Hooley E, Clarke AR, Thomas S, Brady RL, J Mol Biol. 2006 Mar 17;357(1):263-74. Epub 2006 Jan 6. PMID:16413579
Page seeded by OCA on Sun Mar 23 14:35:25 2008
