7KS4
Thermus Phage P74-26 Large Terminase ATPase domain with partially bound ADP
Summary for 7KS4
| Entry DOI | 10.2210/pdb7ks4/pdb |
| Descriptor | Phage terminase large subunit, SULFATE ION, ADENOSINE-5'-DIPHOSPHATE, ... (5 entities in total) |
| Functional Keywords | phage large terminase, asce atpase, viral protein |
| Biological source | Thermus phage P7426 |
| Total number of polymer chains | 1 |
| Total formula weight | 32704.68 |
| Authors | |
| Primary citation | Pajak, J.,Atz, R.,Hilbert, B.J.,Morais, M.C.,Kelch, B.A.,Jardine, P.J.,Arya, G. Viral packaging ATPases utilize a glutamate switch to couple ATPase activity and DNA translocation. Proc.Natl.Acad.Sci.USA, 118:-, 2021 Cited by PubMed Abstract: Many viruses utilize ringed packaging ATPases to translocate double-stranded DNA into procapsids during replication. A critical step in the mechanochemical cycle of such ATPases is ATP binding, which causes a subunit within the motor to grip DNA tightly. Here, we probe the underlying molecular mechanism by which ATP binding is coupled to DNA gripping and show that a glutamate-switch residue found in AAA+ enzymes is central to this coupling in viral packaging ATPases. Using free-energy landscapes computed through molecular dynamics simulations, we determined the stable conformational state of the ATPase active site in ATP- and ADP-bound states. Our results show that the catalytic glutamate residue transitions from an active to an inactive pose upon ATP hydrolysis and that a residue assigned as the glutamate switch is necessary for regulating this transition. Furthermore, we identified via mutual information analyses the intramolecular signaling pathway mediated by the glutamate switch that is responsible for coupling ATP binding to conformational transitions of DNA-gripping motifs. We corroborated these predictions with both structural and functional experimental measurements. Specifically, we showed that the crystal structure of the ADP-bound P74-26 packaging ATPase is consistent with the structural coupling predicted from simulations, and we further showed that disrupting the predicted signaling pathway indeed decouples ATPase activity from DNA translocation activity in the φ29 DNA packaging motor. Our work thus establishes a signaling pathway that couples chemical and mechanical events in viral DNA packaging motors. PubMed: 33888587DOI: 10.1073/pnas.2024928118 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.887 Å) |
Structure validation
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