Loading
PDBj
MenuPDBj@FacebookPDBj@X(formerly Twitter)PDBj@BlueSkyPDBj@YouTubewwPDB FoundationwwPDBDonate
RCSB PDBPDBeBMRBAdv. SearchSearch help

4TPS

Sporulation Inhibitor of DNA Replication, SirA, in complex with Domain I of DnaA

Summary for 4TPS
Entry DOI10.2210/pdb4tps/pdb
DescriptorSporulation inhibitor of replication protein SirA, Chromosomal replication initiator protein DnaA, BETA-MERCAPTOETHANOL, ... (5 entities in total)
Functional Keywordsreplication, sporulation, inhibitory complex
Biological sourceBacillus subtilis
More
Cellular locationCytoplasm (By similarity): P05648
Total number of polymer chains4
Total formula weight57150.64
Authors
Jameson, K.H.,Turkenburg, J.P.,Fogg, M.J.,Grahl, A.,Wilkinson, A.J. (deposition date: 2014-06-09, release date: 2014-07-30, Last modification date: 2024-04-03)
Primary citationJameson, K.H.,Rostami, N.,Fogg, M.J.,Turkenburg, J.P.,Grahl, A.,Murray, H.,Wilkinson, A.J.
Structure and interactions of the Bacillus subtilis sporulation inhibitor of DNA replication, SirA, with domain I of DnaA.
Mol.Microbiol., 93:975-991, 2014
Cited by
PubMed Abstract: Chromosome copy number in cells is controlled so that the frequency of initiation of DNA replication matches that of cell division. In bacteria, this is achieved through regulation of the interaction between the initiator protein DnaA and specific DNA elements arrayed at the origin of replication. DnaA assembles at the origin and promotes DNA unwinding and the assembly of a replication initiation complex. SirA is a DnaA-interacting protein that inhibits initiation of replication in diploid Bacillus subtilis cells committed to the developmental pathway leading to formation of a dormant spore. Here we present the crystal structure of SirA in complex with the N-terminal domain of DnaA revealing a heterodimeric complex. The interacting surfaces of both proteins are α-helical with predominantly apolar side-chains packing in a hydrophobic interface. Site-directed mutagenesis experiments confirm the importance of this interface for the interaction of the two proteins in vitro and in vivo. Localization of GFP-SirA indicates that the protein accumulates at the replisome in sporulating cells, likely through a direct interaction with DnaA. The SirA interacting surface of DnaA corresponds closely to the HobA-interacting surface of DnaA from Helicobacter pylori even though HobA is an activator of DnaA and SirA is an inhibitor.
PubMed: 25041308
DOI: 10.1111/mmi.12713
PDB entries with the same primary citation
Experimental method
X-RAY DIFFRACTION (1.65 Å)
Structure validation

247536

PDB entries from 2026-01-14

PDB statisticsPDBj update infoContact PDBjnumon