title: Crenarchaeal chromatin proteins Cren7 and Sul7 compact DNA by inducing rigid bends.
abstract: Archaeal chromatin proteins share molecular and functional similarities with both bacterial and eukaryotic chromatin proteins. These proteins play an important role in functionally organizing the genomic DNA into a compact nucleoid. Cren7 and Sul7 are two crenarchaeal nucleoid-associated proteins, which are structurally homologous, but not conserved at the sequence level. Co-crystal structures have shown that these two proteins induce a sharp bend on binding to DNA. In this study, we have investigated the architectural properties of these proteins using atomic force microscopy, molecular dynamics simulations and magnetic tweezers. We demonstrate that Cren7 and Sul7 both compact DNA molecules to a similar extent. Using a theoretical model, we quantify the number of individual proteins bound to the DNA as a function of protein concentration and show that forces up to 3.5 pN do not affect this binding. Moreover, we investigate the flexibility of the bending angle induced by Cren7 and Sul7 and show that the protein-DNA complexes differ in flexibility from analogous bacterial and eukaryotic DNA-bending proteins.
authors.affiliation: Molecular Genetics, Leiden Institute of Chemistry and Cell Observatory, Physics of Life Processes, Leiden Institute of Physics and Cell Observatory, Leiden University, 2333 CC Leiden, The Netherlands.
authors.forename: Rosalie P C
authors.initials: RP
authors.lastname: Driessen
authors.forename: He
authors.initials: H
authors.lastname: Meng
authors.forename: Gorle
authors.initials: G
authors.lastname: Suresh
authors.forename: Rajesh
authors.initials: R
authors.lastname: Shahapure
authors.forename: Giovanni
authors.initials: G
authors.lastname: Lanzani
authors.forename: U Deva
authors.initials: UD
authors.lastname: Priyakumar
authors.forename: Malcolm F
authors.initials: MF
authors.lastname: White
authors.forename: Helmut
authors.initials: H
authors.lastname: Schiessel
authors.forename: John
authors.initials: J
authors.lastname: van Noort
authors.forename: Remus Th
authors.initials: RT
authors.lastname: Dame
mesh_terms: D019843:Archaeal Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure; D004268:DNA-Binding Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D056004:Molecular Dynamics Simulation; D009690:Nucleic Acid Conformation; D048229:Sulfolobus solfataricus
chemical_list: D019843:Archaeal Proteins; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D004247:DNA