| Structural highlights
4doc is a 4 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , , , |
| NonStd Res: | |
| Related: | 4do9, 4doa, 4dob |
| Gene: | POLB (HUMAN) |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[DPOLB_HUMAN] 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.[1] [2] [3] [4]
Publication Abstract from PubMed
Deoxynucleoside 5'-triphosphate analogues in which the beta,gamma-bridging oxygen has been replaced with a CXY group are useful chemical probes to investigate DNA polymerase catalytic and base-selection mechanisms. A limitation of such probes has been that conventional synthetic methods generate a mixture of diastereomers when the bridging carbon substitution is nonequivalent (X not equal Y). We report here a general solution to this long-standing problem with four examples of beta,gamma-CXY dNTP diastereomers: (S)- and (R)-beta,gamma-CHCl-dGTP (12a-1/12a-2) and (S)- and (R)-beta,gamma-CHF-dGTP (12b-1/12b-2). Central to their preparation was conversion of the prochiral parent bisphosphonic acids to the P,C-dimorpholinamide derivatives 7 of their (R)-mandelic acid monoesters, which provided access to the individual diastereomers 7a-1, 7a-2, 7b-1, and 7b-2 by preparative HPLC. Selective acidic hydrolysis of the P-N bond then afforded "portal" diastereomers, which were readily coupled to morpholine-activated dGMP. Removal of the chiral auxiliary by H(2) (Pd/C) gave the four individual diastereomeric nucleotides 12, which were characterized by (31)P, (1)H, and (19)F NMR spectroscopy and by mass spectrometry. After treatment with Chelex-100 to remove traces of paramagnetic ions, at pH approximately 10 the diastereomer pairs 12a,b exhibit discrete P(alpha) and P(beta)(31)P resonances. The more upfield P(alpha) and more downfield P(beta) resonances (and also the more upfield (19)F NMR resonance in 12b) are assigned to the R configuration at the P(beta)-CHX-P(gamma) carbons on the basis of the absolute configurations of the individual diastereomers as determined from the X-ray crystallographic structures of their ternary complexes with DNA and polymerase beta.
beta,gamma-CHF- and beta,gamma-CHCl-dGTP Diastereomers: Synthesis, Discrete (31)P NMR Signatures, and Absolute Configurations of New Stereochemical Probes for DNA Polymerases.,Wu Y, Zakharova VM, Kashemirov BA, Goodman MF, Batra VK, Wilson SH, McKenna CE J Am Chem Soc. 2012 May 30;134(21):8734-7. Epub 2012 May 18. PMID:22397499[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Bennett RA, Wilson DM 3rd, Wong D, Demple B. Interaction of human apurinic endonuclease and DNA polymerase beta in the base excision repair pathway. Proc Natl Acad Sci U S A. 1997 Jul 8;94(14):7166-9. PMID:9207062
- ↑ Matsumoto Y, Kim K, Katz DS, Feng JA. Catalytic center of DNA polymerase beta for excision of deoxyribose phosphate groups. Biochemistry. 1998 May 5;37(18):6456-64. PMID:9572863 doi:10.1021/bi9727545
- ↑ DeMott MS, Beyret E, Wong D, Bales BC, Hwang JT, Greenberg MM, Demple B. Covalent trapping of human DNA polymerase beta by the oxidative DNA lesion 2-deoxyribonolactone. J Biol Chem. 2002 Mar 8;277(10):7637-40. Epub 2002 Jan 22. PMID:11805079 doi:10.1074/jbc.C100577200
- ↑ Parsons JL, Dianova II, Khoronenkova SV, Edelmann MJ, Kessler BM, Dianov GL. USP47 is a deubiquitylating enzyme that regulates base excision repair by controlling steady-state levels of DNA polymerase beta. Mol Cell. 2011 Mar 4;41(5):609-15. doi: 10.1016/j.molcel.2011.02.016. PMID:21362556 doi:10.1016/j.molcel.2011.02.016
- ↑ Wu Y, Zakharova VM, Kashemirov BA, Goodman MF, Batra VK, Wilson SH, McKenna CE. beta,gamma-CHF- and beta,gamma-CHCl-dGTP Diastereomers: Synthesis, Discrete (31)P NMR Signatures, and Absolute Configurations of New Stereochemical Probes for DNA Polymerases. J Am Chem Soc. 2012 May 30;134(21):8734-7. Epub 2012 May 18. PMID:22397499 doi:10.1021/ja300218x
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