Structural highlights
Function
[DNBI_BPT7] Single-stranded DNA-binding protein that eliminates secondary structure in long ssDNA formed on the lagging strand of the replication fork. Stimulates DNA polymerase activity and increases the efficiency of RNA primer synthesis by interacting with the DNA polymerase and the helicase/primase protein gp4. Disrupts loops, hairpins and other secondary structures present on ssDNA to reduce and eliminate pausing of viral DNA polymerase at specific sites during elongation.[1] [2] [3]
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
The gene 2.5 protein (gp2.5) of bacteriophage T7 is a single-stranded DNA (ssDNA) binding protein that has essential roles in DNA replication and recombination. In addition to binding DNA, gp2.5 physically interacts with T7 DNA polymerase and T7 primase-helicase during replication to coordinate events at the replication fork. We have determined a 1.9-A crystal structure of gp2.5 and show that it has a conserved OB-fold (oligosaccharide/oligonucleotide binding fold) that is well adapted for interactions with ssDNA. Superposition of the OB-folds of gp2.5 and other ssDNA binding proteins reveals a conserved patch of aromatic residues that stack against the bases of ssDNA in the other crystal structures, suggesting that gp2.5 binds to ssDNA in a similar manner. An acidic C-terminal extension of the gp2.5 protein, which is required for dimer formation and for interactions with the T7 DNA polymerase and the primase-helicase, appears to be flexible and may act as a switch that modulates the DNA binding affinity of gp2.5.
Structure of the gene 2.5 protein, a single-stranded DNA binding protein encoded by bacteriophage T7.,Hollis T, Stattel JM, Walther DS, Richardson CC, Ellenberger T Proc Natl Acad Sci U S A. 2001 Aug 14;98(17):9557-62. Epub 2001 Jul 31. PMID:11481454[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Kim YT, Tabor S, Bortner C, Griffith JD, Richardson CC. Purification and characterization of the bacteriophage T7 gene 2.5 protein. A single-stranded DNA-binding protein. J Biol Chem. 1992 Jul 25;267(21):15022-31. PMID:1634538
- ↑ Marintcheva B, Hamdan SM, Lee SJ, Richardson CC. Essential residues in the C terminus of the bacteriophage T7 gene 2.5 single-stranded DNA-binding protein. J Biol Chem. 2006 Sep 1;281(35):25831-40. Epub 2006 Jun 28. PMID:16807232 doi:http://dx.doi.org/10.1074/jbc.M604601200
- ↑ Kim YT, Richardson CC. Acidic carboxyl-terminal domain of gene 2.5 protein of bacteriophage T7 is essential for protein-protein interactions. J Biol Chem. 1994 Feb 18;269(7):5270-8. PMID:8106511
- ↑ Hollis T, Stattel JM, Walther DS, Richardson CC, Ellenberger T. Structure of the gene 2.5 protein, a single-stranded DNA binding protein encoded by bacteriophage T7. Proc Natl Acad Sci U S A. 2001 Aug 14;98(17):9557-62. Epub 2001 Jul 31. PMID:11481454 doi:10.1073/pnas.171317698
