title: Solubility and charge inversion of complexes of DNA and basic proteins.
abstract: The basic proteins, protamines and histones H1, are known to condense DNA in vivo. We examine here their ability to condense and solubilize in vitro linear DNA [and a synthetic polyanion, Poly(Styrene-Sulfonate) or PSS] at low ionic concentrations by varying the charge concentration ratio. Phase separation is observed in a very narrow range of ratios for short DNA and PSS; on both sides of this range, polydisperse and charged complexes are formed. A charge inversion is detected. For long DNA chains however, a different behavior is observed: the complexes are not soluble in excess of proteins.
authors.affiliation: Laboratoire de Physique des Solides, CNRS UMR 8502, Université Paris Sud, 91405 Orsay Cedex, France. raspaud@lps.u-psud.fr
authors.forename: Eric
authors.initials: E
authors.lastname: Raspaud
authors.forename: J
authors.initials: J
authors.lastname: Pelta
authors.forename: M
authors.initials: M
authors.lastname: de Frutos
authors.forename: F
authors.initials: F
authors.lastname: Livolant
mesh_terms: D001665:Binding Sites; D003198:Computer Simulation; D004247:DNA / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D011485:Protein Binding; D012995:Solubility; D055672:Static Electricity
chemical_list: D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D004247:DNA