title: The helicase-like domains of type III restriction enzymes trigger long-range diffusion along DNA.
abstract: Helicases are ubiquitous adenosine triphosphatases (ATPases) with widespread roles in genome metabolism. Here, we report a previously undescribed functionality for ATPases with helicase-like domains; namely, that ATP hydrolysis can trigger ATP-independent long-range protein diffusion on DNA in one dimension (1D). Specifically, using single-molecule fluorescence microscopy we show that the Type III restriction enzyme EcoP15I uses its ATPase to switch into a distinct structural state that diffuses on DNA over long distances and long times. The switching occurs only upon binding to the target site and requires hydrolysis of ~30 ATPs. We define the mechanism for these enzymes and show how ATPase activity is involved in DNA target site verification and 1D signaling, roles that are common in DNA metabolism: for example, in nucleotide excision and mismatch repair.
authors.affiliation: DNA motors group, Biotechnology Center, Technische Universität Dresden, 01062 Dresden, Germany.
authors.forename: Friedrich W
authors.initials: FW
authors.lastname: Schwarz
authors.forename: Júlia
authors.initials: J
authors.lastname: Tóth
authors.forename: Kara
authors.initials: K
authors.lastname: van Aelst
authors.forename: Guanshen
authors.initials: G
authors.lastname: Cui
authors.forename: Sylvia
authors.initials: S
authors.lastname: Clausing
authors.forename: Mark D
authors.initials: MD
authors.lastname: Szczelkun
authors.forename: Ralf
authors.initials: R
authors.lastname: Seidel
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D053837:DNA Cleavage; D004265:DNA Helicases / Q000737:chemistry / Q000378:metabolism*; D015263:Deoxyribonucleases, Type III Site-Specific / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D008856:Microscopy, Fluorescence / Q000379:methods; D009690:Nucleic Acid Conformation; D017434:Protein Structure, Tertiary
chemical_list: D000255:Adenosine Triphosphate; D004247:DNA; C023451:endodeoxyribonuclease EcoP15I; D015263:Deoxyribonucleases, Type III Site-Specific; D004265:DNA Helicases