Solubility and charge inversion of complexes of DNA and basic proteins.
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.
Raspaud
Eric
E
Laboratoire de Physique des Solides, CNRS UMR 8502, Université Paris Sud, 91405 Orsay Cedex, France. raspaud@lps.u-psud.fr
Pelta
J
J
de Frutos
M
M
Livolant
F
F
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
D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D004247:DNA