2ccz
From Proteopedia
Crystal structure of E. coli primosomol protein PriB bound to ssDNA
Structural highlights
FunctionPRIB_ECOLI Binds single-stranded DNA at the primosome assembly site (PAS). During primosome assembly it facilitates the complex formation between PriA and DnaT.[1] [2] [3] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedPriB is a primosomal protein required for replication restart in Escherichia coli. PriB stimulates PriA helicase activity via interaction with single-stranded DNA (ssDNA), but the molecular details of this interaction remain unclear. Here, we report the crystal structure of PriB complexed with a 15 bases oligonucleotide (dT15) at 2.7 A resolution. PriB shares structural similarity with the E.coli ssDNA-binding protein (EcoSSB). However, the structure of the PriB-dT15 complex reveals that PriB binds ssDNA differently. Results from filter-binding assays show that PriB-ssDNA interaction is salt-sensitive and cooperative. Mutational analysis suggests that the loop L45 plays an important role in ssDNA binding. Based on the crystal structure and biochemical analyses, we propose a cooperative mechanism for the binding of PriB to ssDNA and a model for the assembly of the PriA-PriB-ssDNA complex. This report presents the first structure of a replication restart primosomal protein complexed with DNA, and a novel model that explains the interactions between a dimeric oligonucleotide-binding-fold protein and ssDNA. Complexed crystal structure of replication restart primosome protein PriB reveals a novel single-stranded DNA-binding mode.,Huang CY, Hsu CH, Sun YJ, Wu HN, Hsiao CD Nucleic Acids Res. 2006;34(14):3878-86. Epub 2006 Aug 9. PMID:16899446[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|