Osmotic effectors and DNA structure: effect of glycine on precipitation of DNA by multivalent cations.
We have investigated the effect of glycine (an organic osmolyte) on DNA precipitation induced by spermine4+, spermidine3+ and Tb3+ addition, using circular dichroism (CD), UV spectroscopy (UV), and electric linear dichroism (ELD) techniques. DNA precipitation by the three compounds is perturbed by glycine: more spermine4+, spermidine3+ and Tb3+ must be added to obtain the same extent of precipitation as compared to the behaviour in absence of this organic osmolyte. It seems that glycine has a general effect on the DNA environment. Calculations based on experimental results and Manning's counterion condensation theory show that glycine could modify the electrostatic environment of DNA as a consequence of a change in dielectric constant.
Laboratoire de Chimie Macromoléculaire et Chimie Physique, Université de Liège, Sart-Tilman (B6), Belgium.
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Flock
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Labarbe
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Houssier
D000818:Animals; D002412:Cations / Q000737:chemistry; D004247:DNA / Q000737:chemistry* / Q000187:drug effects; D005998:Glycine / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009997:Osmotic Pressure; D011067:Poly dA-dT / Q000737:chemistry; D013095:Spermidine / Q000737:chemistry; D013096:Spermine / Q000737:chemistry; D013725:Terbium / Q000737:chemistry
D002412:Cations; D013725:Terbium; D011067:Poly dA-dT; D013096:Spermine; C067490:terbium chloride; D004247:DNA; D005998:Glycine; D013095:Spermidine