Summary information and primary citation
- PDB-id
- 1mq3; SNAP-derived features in text and JSON formats;
DNAproDB
- Class
- transferase-DNA
- Method
- X-ray (2.8 Å)
- Summary
- Human DNA polymerase beta complexed with gapped DNA containing an 8-oxo-7,8-dihydro-guanine template paired with dctp
- Reference
- Krahn JM, Beard WA, Miller H, Grollman AP, Wilson SH (2003): "Structure of DNA Polymerase beta with the Mutagenic DNA Lesion 8-oxodeoxyguanine Reveals
Structural Insights into its Coding Potential." Structure, 11, 121-127. doi: 10.1016/S0969-2126(02)00930-9.
- Abstract
- Oxidative damage to DNA generates 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG). During DNA replication and repair synthesis, 8-oxodG can pair with cytosine or adenine. The ability to accurately replicate through this lesion depends on the DNA polymerase. We report the first structure of a polymerase with a promutagenic DNA lesion, 8-oxodG, in the confines of its active site. The modified guanine residue is in an anti conformation and forms Watson-Crick hydrogen bonds with an incoming dCTP. To accommodate the oxygen at C8, the 5'-phosphate backbone of the templating nucleotide flips 180 degrees. Thus, the flexibility of the template sugar-phosphate backbone near the polymerase active site is one parameter that influences the anti-syn equilibrium of 8-oxodG. Our results provide insights into the mechanisms employed by polymerases to select the complementary dNTP.
