Structural highlights
2jl9 is a 3 chain structure with sequence from Bpph6. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
|
| Related: | 1uvn, 1uvj, 1hht, 1hi1, 1wac, 1uvm, 1uvk, 1hhs, 1hi0, 1uvi, 1uvl, 1hi8 |
| Activity: | RNA-directed RNA polymerase, with EC number 2.7.7.48 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum |
Publication Abstract from PubMed
The biological role of manganese (Mn(2+)) has been a long-standing puzzle, since at low concentrations it activates several polymerases whilst at higher concentrations it inhibits. Viral RNA polymerases possess a common architecture, reminiscent of a closed right hand. The RNA-dependent RNA polymerase (RdRp) of bacteriophage 6 is one of the best understood examples of this important class of polymerases. We have probed the role of Mn(2+) by biochemical, biophysical and structural analyses of the wild-type enzyme and of a mutant form with an altered Mn(2+)-binding site (E491 to Q). The E491Q mutant has much reduced affinity for Mn(2+), reduced RNA binding and a compromised elongation rate. Loss of Mn(2+) binding structurally stabilizes the enzyme. These data and a re-examination of the structures of other viral RNA polymerases clarify the role of manganese in the activation of polymerization: Mn(2+) coordination of a catalytic aspartate is necessary to allow the active site to properly engage with the triphosphates of the incoming NTPs. The structural flexibility caused by Mn(2+) is also important for the enzyme dynamics, explaining the requirement for manganese throughout RNA polymerization.
Structural explanation for the role of Mn2+ in the activity of {phi}6 RNA-dependent RNA polymerase.,Poranen MM, Salgado PS, Koivunen MR, Wright S, Bamford DH, Stuart DI, Grimes JM Nucleic Acids Res. 2008 Oct 21. PMID:18940872[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Poranen MM, Salgado PS, Koivunen MR, Wright S, Bamford DH, Stuart DI, Grimes JM. Structural explanation for the role of Mn2+ in the activity of {phi}6 RNA-dependent RNA polymerase. Nucleic Acids Res. 2008 Oct 21. PMID:18940872 doi:gkn632
