Journal of
Biophysics and Structural Biology

  • Abbreviation: J. Biophys. Struct. Biol.
  • Language: English
  • ISSN: 2141-2200
  • DOI: 10.5897/JBSB
  • Start Year: 2009
  • Published Articles: 25

Full Length Research Paper

A thermodynamic investigation of bovine carbonic anhydrase II interaction with cobalt ion at 300 and 310K

G. Rezaei Behbehani1*, A. Divsalar2,3, A. A. Saboury2 and Z. Rezaei4
1Chemistry Department, Imam Khomeini International University, Qazvin Iran. 2Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran. 3Department of Biological Sciences, Tarbiat Moallem University, Tehran, Iran. 4Chemistry Department, Islamic Azad University, Gachsaran, Iran.
Email: [email protected]

  •  Accepted: 18 November 2009
  •  Published: 31 December 2009

Abstract

A thermodynamic study on the interaction of bovine carbonic anhydrase II, CAII, with cobalt ions was studied by using isothermal titration calorimetry (ITC) at  27 and 37°C in tris buffer solution at pH = 7.5. The heats of Co2++CAII interaction are reported and analysed in terms of the new solvation theory. It was indicated that there are three identical and non-cooperative sites for Co2+. The binding of a cobalt ion is exothermic with dissociation equilibrium constants of 81.306 and 99.126 µM at 27 and 37°C respectively. The binding of cobalt ions can cause some changes in structure of enzyme, which results in a decrease in the activity and stability of the enzyme.

 

Key words: Bovine carbonic anhydrase, cobalt ion, isothermal titration calorimetry.