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1jn3

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Revision as of 06:42, 11 August 2021

FIDELITY PROPERTIES AND STRUCTURE OF M282L MUTATOR MUTANT OF DNA POLYMERASE: SUBTLE STRUCTURAL CHANGES INFLUENCE THE MECHANISM OF NUCLEOTIDE DISCRIMINATION

Structural highlights

1jn3 is a 1 chain structure with sequence from Buffalo rat. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	1rpl
Activity:	DNA-directed DNA polymerase, with EC number 2.7.7.7
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[DPOLB_RAT] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

DNA polymerase beta (pol beta) offers a simple system to examine the role of polymerase structure in the fidelity of DNA synthesis. In this study, the M282L variant of pol beta (M282Lbeta) was identified using an in vivo genetic screen. Met282, which does not contact the DNA template or the incoming deoxynucleoside triphosphate (dNTP) substrate, is located on alpha-helix N of pol beta. This mutant enzyme demonstrates increased mutagenesis in both in vivo and in vitro assays. M282Lbeta has a 7.5-fold higher mutation frequency than wild-type pol beta; M282Lbeta commits a variety of base substitution and frameshift errors. Transient-state kinetic methods were used to investigate the mechanism of intrinsic mutator activity of M282Lbeta. Results show an 11-fold decrease in dNTP substrate discrimination at the level of ground-state binding. However, during the protein conformational change and/or phosphodiester bond formation, the nucleotide discrimination is improved. X-ray crystallography was utilized to gain insights into the structural basis of the decreased DNA synthesis fidelity. Most of the structural changes are localized to site 282 and the surrounding region in the C-terminal part of the 31-kDa domain. Repositioning of mostly hydrophobic amino acid residues in the core of the C-terminal portion generates a protein with enhanced stability. The combination of structural and equilibrium unfolding data suggests that the mechanism of nucleotide discrimination is possibly affected by the compacting of the hydrophobic core around residue Leu282. Subsequent movement of an adjacent surface residue, Arg283, produces a slight increase in volume of the pocket that may accommodate the incoming correct base pair. The structural changes of M282Lbeta ultimately lead to an overall reduction in polymerase fidelity.

A DNA polymerase beta mutator mutant with reduced nucleotide discrimination and increased protein stability.,Shah AM, Conn DA, Li SX, Capaldi A, Jager J, Sweasy JB Biochemistry. 2001 Sep 25;40(38):11372-81. PMID:11560485^[1]

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

References

↑ Shah AM, Conn DA, Li SX, Capaldi A, Jager J, Sweasy JB. A DNA polymerase beta mutator mutant with reduced nucleotide discrimination and increased protein stability. Biochemistry. 2001 Sep 25;40(38):11372-81. PMID:11560485

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1jn3"

@@ Line 3: / Line 3: @@
 <StructureSection load='1jn3' size='340' side='right'caption='[[1jn3]], [[Resolution|resolution]] 2.35&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[1jn3]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Buffalo_rat Buffalo rat]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JN3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1JN3 FirstGlance]. <br>
+<table><tr><td colspan='2'>[[1jn3]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Buffalo_rat Buffalo rat]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JN3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1JN3 FirstGlance]. <br>
-</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1rpl|1rpl]]</td></tr>
+</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1rpl|1rpl]]</div></td></tr>
-<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] </span></td></tr>
+<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] </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=1jn3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jn3 OCA], [http://pdbe.org/1jn3 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1jn3 RCSB], [http://www.ebi.ac.uk/pdbsum/1jn3 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1jn3 ProSAT]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1jn3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jn3 OCA], [https://pdbe.org/1jn3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1jn3 RCSB], [https://www.ebi.ac.uk/pdbsum/1jn3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1jn3 ProSAT]</span></td></tr>
 </table>
 == Function ==
-[[http://www.uniprot.org/uniprot/DPOLB_RAT DPOLB_RAT]] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.
+[[https://www.uniprot.org/uniprot/DPOLB_RAT DPOLB_RAT]] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]
@@ Line 29: / Line 29: @@
 </div>
 <div class="pdbe-citations 1jn3" style="background-color:#fffaf0;"></div>
-==See Also==
-*[[DNA polymerase 3D structures|DNA polymerase 3D structures]]
 == References ==
 <references/>

1jn3

From Proteopedia

Revision as of 06:42, 11 August 2021

FIDELITY PROPERTIES AND STRUCTURE OF M282L MUTATOR MUTANT OF DNA POLYMERASE: SUBTLE STRUCTURAL CHANGES INFLUENCE THE MECHANISM OF NUCLEOTIDE DISCRIMINATION

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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