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4hsb

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Revision as of 16:27, 4 August 2016

S. pombe 3-methyladenine DNA glycosylase-like protein Mag2 bound to damaged DNA

Structural highlights

4hsb is a 3 chain structure with sequence from Fission yeast. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
NonStd Res:
Related:	3s6i
Gene:	SPBC23G7.11 (Fission yeast)
Activity:	DNA-3-methyladenine glycosylase II, with EC number 3.2.2.21
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[MAG2_SCHPO] Invlved in base excision repair of methyl methanesulfonate-damaged DNA by hydrolysis of the deoxyribose N-glycosidic bond to excise 3-methyladenine or 7-methyladenine from the damaged DNA polymer formed by alkylation lesions.^[1]

Publication Abstract from PubMed

Schizosaccharomyces pombe contains two paralogous proteins, Mag1 and Mag2, related to the helix-hairpin-helix (HhH) superfamily of alkylpurine DNA glycosylases from yeast and bacteria. Phylogenetic analysis of related proteins from four Schizosaccharomyces and other fungal species shows that the Mag1/Mag2 duplication is unique to the genus Schizosaccharomyces and most likely occurred in its ancestor. Mag1 excises N3- and N7-alkylguanines and 1,N(6)-ethenoadenine from DNA, whereas Mag2 has been reported to have no detectible alkylpurine base excision activity despite high sequence and active site similarity to Mag1. To understand this discrepancy we determined the crystal structure of Mag2 bound to abasic DNA and compared it to our previously determined Mag1-DNA structure. In contrast to Mag1, Mag2 does not flip the abasic moiety into the active site or stabilize the DNA strand 5' to the lesion, suggesting that it is incapable of forming a catalytically competent protein-DNA complex. Subtle differences in Mag1 and Mag2 interactions with the DNA duplex illustrate how Mag2 can stall at damage sites without fully engaging the lesion. We tested our structural predictions by mutational analysis of base excision and found a single amino acid responsible at least in part for Mag2's lack of activity. Substitution of Mag2 Asp56, which caps the helix at the base of the DNA intercalation loop, with the corresponding serine residue in Mag1 endows Mag2 with varepsilonA excision activity comparable to Mag1. This work provides novel insight into the chemical and physical determinants by which the HhH glycosylases engage DNA in a catalytically productive manner.

Non-productive DNA damage binding by DNA glycosylase-like protein Mag2 from Schizosaccharomyces pombe.,Adhikary S, Cato MC, McGary KL, Rokas A, Eichman BF DNA Repair (Amst). 2012 Dec 27. pii: S1568-7864(12)00290-X. doi:, 10.1016/j.dnarep.2012.12.001. PMID:23273506^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Kanamitsu K, Tanihigashi H, Tanita Y, Inatani S, Ikeda S. Involvement of 3-methyladenine DNA glycosylases Mag1p and Mag2p in base excision repair of methyl methanesulfonate-damaged DNA in the fission yeast Schizosaccharomyces pombe. Genes Genet Syst. 2007 Dec;82(6):489-94. PMID:18270439
↑ Adhikary S, Cato MC, McGary KL, Rokas A, Eichman BF. Non-productive DNA damage binding by DNA glycosylase-like protein Mag2 from Schizosaccharomyces pombe. DNA Repair (Amst). 2012 Dec 27. pii: S1568-7864(12)00290-X. doi:, 10.1016/j.dnarep.2012.12.001. PMID:23273506 doi:http://dx.doi.org/10.1016/j.dnarep.2012.12.001

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4hsb"

@@ Line 1: / Line 1: @@
 ==S. pombe 3-methyladenine DNA glycosylase-like protein Mag2 bound to damaged DNA==
 <StructureSection load='4hsb' size='340' side='right' caption='[[4hsb]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
@@ Line 8: / Line 9: @@
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">SPBC23G7.11 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast])</td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA-3-methyladenine_glycosylase_II DNA-3-methyladenine glycosylase II], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.21 3.2.2.21] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4hsb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4hsb OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4hsb RCSB], [http://www.ebi.ac.uk/pdbsum/4hsb PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4hsb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4hsb OCA], [http://pdbe.org/4hsb PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4hsb RCSB], [http://www.ebi.ac.uk/pdbsum/4hsb PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4hsb ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 20: / Line 21: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4hsb" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

4hsb

From Proteopedia

Revision as of 16:27, 4 August 2016

S. pombe 3-methyladenine DNA glycosylase-like protein Mag2 bound to damaged DNA

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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