{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["121(23)"],"submitter":["Singh A"],"pubmed_abstract":["Protein allostery requires a communication channel for functional regulation between distal sites within a protein. In the molecular chaperone Hsp70, a two-domain enzyme, the ATP/ADP status of an N-terminal nucleotide-binding domain regulates the substrate affinity of a C-terminal substrate-binding domain. Recently available three-dimensional structures of Hsp70 in ATP/ADP states have provided deep insights into molecular pathways of allosteric signals. However, direct mechanical probing of long-range allosteric coupling between the ATP hydrolysis step and domain states is missing. Using laser optical tweezers, we examined the mechanical properties of a truncated two-domain DnaK(1-552ye) in apo/ADP/ATP- and peptide-bound states. We find that in the apo and ADP states, DnaK domains are mechanically stable and rigid. However, in the ATP state, substrate-binding domain (SBD)<sup>∗</sup>ye is mechanically destabilized as the result of interdomain docking followed by the unfolding of the α-helical lid. By observing the folding state of the SBD, we could observe the continuous ATP/ADP cycling of the enzyme in real time with a single molecule. The SBD lid closure is strictly coupled to the chemical steps of the ATP hydrolysis cycle even in the presence of peptide substrate."],"journal":["Biophysical journal"],"pagination":["4729-4739"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC9748191"],"repository":["biostudies-literature"],"pubmed_title":["Direct observation of chemo-mechanical coupling in DnaK by single-molecule force experiments."],"pmcid":["PMC9748191"],"pubmed_authors":["Rief M","Zoldak G","Singh A"],"additional_accession":[]},"is_claimable":false,"name":"Direct observation of chemo-mechanical coupling in DnaK by single-molecule force experiments.","description":"Protein allostery requires a communication channel for functional regulation between distal sites within a protein. In the molecular chaperone Hsp70, a two-domain enzyme, the ATP/ADP status of an N-terminal nucleotide-binding domain regulates the substrate affinity of a C-terminal substrate-binding domain. Recently available three-dimensional structures of Hsp70 in ATP/ADP states have provided deep insights into molecular pathways of allosteric signals. However, direct mechanical probing of long-range allosteric coupling between the ATP hydrolysis step and domain states is missing. Using laser optical tweezers, we examined the mechanical properties of a truncated two-domain DnaK(1-552ye) in apo/ADP/ATP- and peptide-bound states. We find that in the apo and ADP states, DnaK domains are mechanically stable and rigid. However, in the ATP state, substrate-binding domain (SBD)<sup>∗</sup>ye is mechanically destabilized as the result of interdomain docking followed by the unfolding of the α-helical lid. By observing the folding state of the SBD, we could observe the continuous ATP/ADP cycling of the enzyme in real time with a single molecule. The SBD lid closure is strictly coupled to the chemical steps of the ATP hydrolysis cycle even in the presence of peptide substrate.","dates":{"release":"2022-01-01T00:00:00Z","publication":"2022 Dec","modification":"2026-05-28T01:35:28.02Z","creation":"2025-04-05T22:22:55.793Z"},"accession":"S-EPMC9748191","cross_references":{"pubmed":["36196054"],"doi":["10.1016/j.bpj.2022.09.042"]}}