Back بوليمراز الدنا Arabic DNK polimeraza BS Polimerasa d'ADN Catalan پۆلیمەرەیزی دی ئێن ئەی CKB DNA polymeráza Czech DNA-polymerase Danish DNA-Polymerasen German DNA πολυμεράση Greek ADN polimerasa Spanish DNA polümeraasid Estonian
| DNA-directed DNA polymerase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 3D structure of the DNA-binding helix-turn-helix motifs in human DNA polymerase beta (based on PDB file 7ICG) | |||||||||
| Identifiers | |||||||||
| EC no. | 2.7.7.7 | ||||||||
| CAS no. | 9012-90-2 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
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A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA. These enzymes are essential for DNA replication and usually work in groups to create two identical DNA duplexes from a single original DNA duplex. During this process, DNA polymerase "reads" the existing DNA strands to create two new strands that match the existing ones.[1][2][3][4][5][6] These enzymes catalyze the chemical reaction
- deoxynucleoside triphosphate + DNAn ⇌ pyrophosphate + DNAn+1.
DNA polymerase adds nucleotides to the three prime (3')-end of a DNA strand, one nucleotide at a time. Every time a cell divides, DNA polymerases are required to duplicate the cell's DNA, so that a copy of the original DNA molecule can be passed to each daughter cell. In this way, genetic information is passed down from generation to generation.
Before replication can take place, an enzyme called helicase unwinds the DNA molecule from its tightly woven form, in the process breaking the hydrogen bonds between the nucleotide bases. This opens up or "unzips" the double-stranded DNA to give two single strands of DNA that can be used as templates for replication in the above reaction.
- ^ Bollum FJ (August 1960). "Calf thymus polymerase". The Journal of Biological Chemistry. 235 (8): 2399–2403. doi:10.1016/S0021-9258(18)64634-4. PMID 13802334.
- ^ Falaschi A, Kornberg A (April 1966). "Biochemical studies of bacterial sporulation. II. Deoxy- ribonucleic acid polymerase in spores of Bacillus subtilis". The Journal of Biological Chemistry. 241 (7): 1478–1482. doi:10.1016/S0021-9258(18)96736-0. PMID 4957767.
- ^ Lehman IR, Bessman MJ, Simms ES, Kornberg A (July 1958). "Enzymatic synthesis of deoxyribonucleic acid. I. Preparation of substrates and partial purification of an enzyme from Escherichia coli". The Journal of Biological Chemistry. 233 (1): 163–170. doi:10.1016/S0021-9258(19)68048-8. PMID 13563462.
- ^ Richardson CC, Schildkraut CL, Aposhian HV, Kornberg A (January 1964). "Enzymatic synthesis of deoxyribonucleic acid. XIV. Further purification and properties of deoxyribonucleic acid polymerase of Escherichia coli". The Journal of Biological Chemistry. 239: 222–232. doi:10.1016/S0021-9258(18)51772-5. PMID 14114848.
- ^ Schachman HK, Adler J, Radding CM, Lehman IR, Kornberg A (November 1960). "Enzymatic synthesis of deoxyribonucleic acid. VII. Synthesis of a polymer of deoxyadenylate and deoxythymidylate". The Journal of Biological Chemistry. 235 (11): 3242–3249. doi:10.1016/S0021-9258(20)81345-3. PMID 13747134.
- ^ Zimmerman BK (May 1966). "Purification and properties of deoxyribonucleic acid polymerase from Micrococcus lysodeikticus". The Journal of Biological Chemistry. 241 (9): 2035–2041. doi:10.1016/S0021-9258(18)96662-7. PMID 5946628.