2pgg
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="2pgg" size="450" color="white" frame="true" align="right" spinBox="true" caption="2pgg, resolution 2.50Å" /> '''Crystal Structure of...)
Next diff →
Revision as of 11:24, 21 November 2007
|
Crystal Structure of a Birnavirus (IBDV) RNA-dependent RNA Polymerase VP1
Overview
Single-subunit polymerases are universally encoded in both cellular, organisms and viruses. Their three-dimensional structures have the shape, of a right-hand with the active site located in the palm region, which has, a topology similar to that of the RNA recognition motif (RRM) found in, many RNA-binding proteins. Considering that polymerases have well, conserved structures, it was surprising that the RNA-dependent RNA, polymerases from birnaviruses, a group of dsRNA viruses, have their, catalytic motifs arranged in a permuted order in sequence. Here we report, the 2.5 A structure of a birnavirus VP1 in which the polymerase palm, subdomain adopts a new active site topology that has not been previously, observed in other polymerases. In addition, the polymerase motif C of VP1, has the sequence of -ADN-, a highly unusual feature for RNA-dependent, polymerases. Through site-directed mutagenesis, we have shown that, changing the VP1 motif C from -ADN- to -GDD- results in a mutant with an, increased RNA synthesis activity. Our results indicate that the active, site topology of VP1 may represent a newly developed branch in polymerase, evolution, and that birnaviruses may have acquired the -ADN- mutation to, control their growth rate.
About this Structure
2PGG is a Single protein structure of sequence from Infectious bursal disease virus. Active as RNA-directed RNA polymerase, with EC number 2.7.7.48 Full crystallographic information is available from OCA.
Reference
The structure of a birnavirus polymerase reveals a distinct active site topology., Pan J, Vakharia VN, Tao YJ, Proc Natl Acad Sci U S A. 2007 May 1;104(18):7385-90. Epub 2007 Apr 24. PMID:17456597
Page seeded by OCA on Wed Nov 21 13:31:37 2007
