7OM0

Structure of Primase-Helicase in SaPI5

Summary for 7OM0

• Entry DOI: 10.2210/pdb7om0/pdb
• EMDB information: 12982
• Descriptor: DNA primase, PHOSPHOAMINOPHOSPHONIC ACID-ADENYLATE ESTER (2 entities in total)
• Functional Keywords: helicase, dna binding, amppnp, replication
• Biological source: Staphylococcus aureus
• Total number of polymer chains: 6
• Total formula weight: 561079.36

Authors

Qiao, C.C.,Mir-Sanchis, I. (deposition date: 2021-05-21, release date: 2022-07-13, Last modification date: 2024-07-10)

Primary citation

Qiao, C.,Debiasi-Anders, G.,Mir-Sanchis, I.
Staphylococcal self-loading helicases couple the staircase mechanism with inter domain high flexibility.
Nucleic Acids Res., 50:8349-8362, 2022

PubMed Abstract: Replication is a crucial cellular process. Replicative helicases unwind DNA providing the template strand to the polymerase and promoting replication fork progression. Helicases are multi-domain proteins which use an ATPase domain to couple ATP hydrolysis with translocation, however the role that the other domains might have during translocation remains elusive. Here, we studied the unexplored self-loading helicases called Reps, present in Staphylococcus aureus pathogenicity islands (SaPIs). Our cryoEM structures of the PriRep5 from SaPI5 (3.3 Å), the Rep1 from SaPI1 (3.9 Å) and Rep1-DNA complex (3.1Å) showed that in both Reps, the C-terminal domain (CTD) undergoes two distinct movements respect the ATPase domain. We experimentally demonstrate both in vitro and in vivo that SaPI-encoded Reps need key amino acids involved in the staircase mechanism of translocation. Additionally, we demonstrate that the CTD's presence is necessary for the maintenance of full ATPase and helicase activities. We speculate that this high interdomain flexibility couples Rep's activities as initiators and as helicases.

PubMed: 35871290
DOI: 10.1093/nar/gkac625

Experimental method

ELECTRON MICROSCOPY (3.1 Å)