title: [Interaction of poly A with phospholipid membranes using IR-spectroscopy].
abstract: IR-spectra of poly-A phosphatidylcholine complexes in D2O were studied. It has been shown that in the absence of Mg2+ the spectrum was a superposition of spectra of poly-A and phosphatidylcholine. Introduction of MgCl2 to the concentration of 0.03 M led to the dramatic decrease of absorbance at 1629 cm-1 characteristic of backbone vibration of adenine. Further increase of the concentration of MgCl2 up to 0.08 M resulted in the additional absorbance maximum at 1627 cm-1. Under a variety of temperatures the position of the maximum did not change. It was assumed that on adding magnesium ions to the "poly-A-lipid" mixture in D2O the components formed a stable complex. At high Mg2+ concentration a partial disarrangement of stacking interactions in poly-A occurred that might be a consequence of the incorporation of nucleic bases into hydrophobic membrane phase.
mesh_terms: D003903:Deuterium; D017666:Deuterium Oxide; D008081:Liposomes; D008274:Magnesium; D008954:Models, Biological; D009690:Nucleic Acid Conformation; D010713:Phosphatidylcholines; D011061:Poly A; D013055:Spectrophotometry, Infrared; D013696:Temperature; D014867:Water
chemical_list: D008081:Liposomes; D010713:Phosphatidylcholines; D014867:Water; D011061:Poly A; D003903:Deuterium; D008274:Magnesium; D017666:Deuterium Oxide
vernacular_title: Izuchenie vzaimodeĭstviia poliA s fosfolipidnymi membranami metodom IK-spektroskopii.