1ay9
From Proteopedia
(New page: 200px<br /><applet load="1ay9" size="450" color="white" frame="true" align="right" spinBox="true" caption="1ay9, resolution 3.0Å" /> '''WILD-TYPE UMUD' FROM ...) |
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| - | [[Image:1ay9.jpg|left|200px]]<br /><applet load="1ay9" size=" | + | [[Image:1ay9.jpg|left|200px]]<br /><applet load="1ay9" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1ay9, resolution 3.0Å" /> | caption="1ay9, resolution 3.0Å" /> | ||
'''WILD-TYPE UMUD' FROM E. COLI'''<br /> | '''WILD-TYPE UMUD' FROM E. COLI'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: Damage induced 'SOS mutagenesis' may occur transiently as part | + | BACKGROUND: Damage induced 'SOS mutagenesis' may occur transiently as part of the global SOS response to DNA damage in bacteria. A key participant in this process is the UmuD protein, which is produced in an inactive from but converted to the active form, UmuD', by a RecA-mediated self-cleavage reaction. UmuD', together with UmuC and activated RecA (RecA*), enables the DNA polymerase III holoenzyme to replicate across chemical and UV induced lesions. The efficiency of this reaction depends on several intricate protein-protein interactions. RESULTS: Recent X-ray crystallographic analysis shows that in addition to forming molecular dimers, the N- and C-terminal tails of UmuD' extend from a globular beta structure to associate and produce crystallized filaments. We have investigated this phenomenon and find that these filaments appear to relate to biological activity. Higher order oligomers are found in solution with UmuD', but not with UmuD nor with a mutant of UmuD' lacking the extended N terminus. Deletion of the N terminus of UmuD' does not affect its ability to form molecular dimers but does severely compromise its ability to interact with a RecA-DNA filament and to participate in mutagenesis. Mutations in the C terminus of UmuD' result in both gain and loss of function for mutagenesis. CONCLUSIONS: The activation of UmuD to UmuD' appears to cause a large conformational change in the protein which allows it to form oligomers in solution at physiologically relevant concentrations. Properties of these oligomers are consistent with the filament structures seen in crystals of UmuD'. |
==About this Structure== | ==About this Structure== | ||
| - | 1AY9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http:// | + | 1AY9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AY9 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Frank, E | + | [[Category: Frank, E G.]] |
| - | [[Category: Hendrickson, W | + | [[Category: Hendrickson, W A.]] |
| - | [[Category: Levine, A | + | [[Category: Levine, A S.]] |
| - | [[Category: Mcdonald, J | + | [[Category: Mcdonald, J P.]] |
| - | [[Category: Peat, T | + | [[Category: Peat, T S.]] |
[[Category: Woodgate, R.]] | [[Category: Woodgate, R.]] | ||
[[Category: dna repair]] | [[Category: dna repair]] | ||
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[[Category: mutagenesis protein]] | [[Category: mutagenesis protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:49:32 2008'' |
Revision as of 09:49, 21 February 2008
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WILD-TYPE UMUD' FROM E. COLI
Overview
BACKGROUND: Damage induced 'SOS mutagenesis' may occur transiently as part of the global SOS response to DNA damage in bacteria. A key participant in this process is the UmuD protein, which is produced in an inactive from but converted to the active form, UmuD', by a RecA-mediated self-cleavage reaction. UmuD', together with UmuC and activated RecA (RecA*), enables the DNA polymerase III holoenzyme to replicate across chemical and UV induced lesions. The efficiency of this reaction depends on several intricate protein-protein interactions. RESULTS: Recent X-ray crystallographic analysis shows that in addition to forming molecular dimers, the N- and C-terminal tails of UmuD' extend from a globular beta structure to associate and produce crystallized filaments. We have investigated this phenomenon and find that these filaments appear to relate to biological activity. Higher order oligomers are found in solution with UmuD', but not with UmuD nor with a mutant of UmuD' lacking the extended N terminus. Deletion of the N terminus of UmuD' does not affect its ability to form molecular dimers but does severely compromise its ability to interact with a RecA-DNA filament and to participate in mutagenesis. Mutations in the C terminus of UmuD' result in both gain and loss of function for mutagenesis. CONCLUSIONS: The activation of UmuD to UmuD' appears to cause a large conformational change in the protein which allows it to form oligomers in solution at physiologically relevant concentrations. Properties of these oligomers are consistent with the filament structures seen in crystals of UmuD'.
About this Structure
1AY9 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
The UmuD' protein filament and its potential role in damage induced mutagenesis., Peat TS, Frank EG, McDonald JP, Levine AS, Woodgate R, Hendrickson WA, Structure. 1996 Dec 15;4(12):1401-12. PMID:8994967
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