title: Single-Molecule DNA Polymerase Dynamics at a Bacterial Replisome in Live Cells.
abstract: PolC is one of two essential replicative DNA polymerases found in the Gram-positive bacterium Bacillus subtilis. The B. subtilis replisome is eukaryotic-like in that it relies on a two DNA polymerase system for chromosomal replication. To quantitatively image how the replicative DNA polymerase PolC functions in B. subtilis, we applied photobleaching-assisted microscopy, three-dimensional superresolution imaging, and single-particle tracking to examine the in vivo behavior of PolC at single-molecule resolution. We report the stoichiometry of PolC proteins within each cell and within each replisome, we elucidate the diffusion characteristics of individual PolC molecules, and we quantify the exchange dynamics for PolC engaged in lagging strand synthesis. We show that PolC is highly dynamic: this DNA polymerase is constantly recruited to and released from a centrally located replisome, providing, to our knowledge, new insight into the organization and dynamics of the replisome in bacterial cells.
authors.affiliation: Department of Chemistry, University of Michigan, Ann Arbor, Michigan.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Chemistry, University of Michigan, Ann Arbor, Michigan.
authors.forename: Yilai
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Jeremy W
authors.initials: JW
authors.lastname: Schroeder
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan. Electronic address: lasimm@umich.edu.
authors.forename: Lyle A
authors.initials: LA
authors.lastname: Simmons
authors.affiliation: Department of Chemistry, University of Michigan, Ann Arbor, Michigan. Electronic address: jsbiteen@umich.edu.
authors.forename: Julie S
authors.initials: JS
authors.lastname: Biteen
mesh_terms: D001412:Bacillus subtilis / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000378:metabolism*; D002470:Cell Survival; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D004058:Diffusion; D021381:Protein Transport
chemical_list: D001426:Bacterial Proteins; C446929:PolC protein, bacteria; D004259:DNA-Directed DNA Polymerase