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Spectrophotometric Determination of Phycobiliprotein Content in Cyanobacterium Synechocystis
Published on: September 11, 2018
[Interaction of Pb(II) ions with C-phycocyanin from Spirulina platensis: effect of ionic strength]
E S Gelagutashvili1, A I Belokobyl'skiĭ, A N Rcheulishvili
1Andronikashvili Institute of Physics, Georgian Academy of Sciences, ul. Tamarashvili 6, Tbilisi, 380077 Georgia.
Abstract:
The effect of Pb(II) ions on C-phycocyanin from Spirulina platensis was studied by the method of fluorescence spectroscopy. The efficiency of quenching was analyzed using the Stern-Volmer relation. Isotherms of adsorption were constructed, and the constants of binding of Pb(II) ions to C-phycocyanin in solutions of varying ionic strength were determined by equilibrium dialysis and atomic absorption spectroscopy. The constants of binding of Pb(II) ions to C-phycocyanin in 2, 20, and 50 mM NaN03 solutions were estimated to be 4.79 x 10(5), 3.63 x 10(5) and 2.82 x 10(5), respectively. It was found that the interaction of Pb(II) ions with C-phycocyanin has a cooperative character at all values of ionic strengths studied.
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