title: Regular oscillatory behavior of aqueous solutions of CuII salts related to effects on equilibrium dynamics of ortho/para hydrogen spin isomers of water.
abstract: Cell surface and growth-related NADH oxidases with protein disulfide-thiol interchange activity, ECTO-NOX, exhibit copper-dependent, clock-related, temperature-independent and entrainable patterns of regular oscillations in the rate of oxidation of NAD(P)H as do aqueous solutions of copper salts. Because of time scale similarities, a basis for the oscillatory patterns in nuclear spin orientations of the hydrogen atoms of the copper-associated water was sought. Extended X-ray absorption fine structure (EXAFS) measurements at 9302 eV on pure water were periodic with a ca. 3.5 min peak to peak separation. Decomposition fits revealed 5 unequally spaced maxima similar to those observed previously for Cu(II)Cl(2) to generate a period length of about 18 min. With D(2)O, the period length was proportionately increased by 30% to 24 min. The redox potential of water and of D(2)O also oscillated with 18 and 24 min period lengths, respectively. Measurements in the middle infrared spectral region above a water sample surface revealed apparent oscillations in the two alternative orientations of the nuclear spins (ortho and para) of the hydrogen atoms of the water or D(2)O with 5 unequally spaced maxima and respective period lengths of 18 and 24 min. Thus, the time keeping oscillations of ECTO-NOX proteins appear to reflect the equilibrium dynamics of ortho-para hydrogen atom spin ratios of water where the presence of metal cations such as Cu(II) in solution determine period length.
authors.affiliation: Department of Medicinal Chemistry and Molecular Pharmacology, Hansen Life Sciences Research Building, Purdue University, 201 S. University Street, West Lafayette, IN 47907-2064, United States. morre@pharmacy.purdue.edu
authors.forename: D J
authors.initials: DJ
authors.lastname: Morré
authors.forename: J
authors.initials: J
authors.lastname: Orczyk
authors.forename: H
authors.initials: H
authors.lastname: Hignite
authors.forename: C
authors.initials: C
authors.lastname: Kim
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D007536:Isomerism; D009097:Multienzyme Complexes / Q000737:chemistry / Q000378:metabolism*; D009243:NAD / Q000737:chemistry* / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D017550:Spectroscopy, Fourier Transform Infrared; D013057:Spectrum Analysis; D014867:Water / Q000737:chemistry*
chemical_list: D009097:Multienzyme Complexes; D014867:Water; D009243:NAD; D003300:Copper; D006859:Hydrogen; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases