2CCZ

Crystal structure of E. coli primosomol protein PriB bound to ssDNA

Summary for 2CCZ

• Entry DOI: 10.2210/pdb2ccz/pdb
• Descriptor: PRIMOSOMAL REPLICATION PROTEIN N, 5'-D(*TP*TP*TP*TP*TP*TP*TP*TP*TP*TP *TP*TP*TP*TP*T)-3' (3 entities in total)
• Functional Keywords: dna/replication, primosome, prib, dna replication, dna repair, dna recombination, ssdna, single-stranded dna, dna-protein complex, dna-replication complex
• Biological source: ESCHERICHIA COLI
• Total number of polymer chains: 3
• Total formula weight: 31889.40

Authors

Huang, C.-Y.,Hsu, C.-H.,Wu, H.-N.,Sun, Y.-J.,Hsiao, C.-D. (deposition date: 2006-01-19, release date: 2006-09-18, Last modification date: 2024-11-13)

Primary citation

Huang, C.-Y.,Hsu, C.-H.,Sun, Y.-J.,Wu, H.-N.,Hsiao, C.-D.
Complexed Crystal Structure of Replication Restart Primsome Protein Prib Reveals a Novel Single-Stranded DNA-Binding Mode.
Nucleic Acids Res., 34:3878-, 2006

PubMed Abstract: PriB 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.

PubMed: 16899446
DOI: 10.1093/NAR/GKL536

Experimental method

X-RAY DIFFRACTION (2.7 Å)