A new multi-binding model for isothermal titration calorimetry analysis of the interaction between adenosine 5′-triphosphate and magnesium ion

An illustration of the interaction model between adenosine 5′-triphosphate and magnesium ion. •We develop a new multi-binding model including Mg2ATP, and Mg(ATP)2.•The ITC data of ATP-Mg2+ binding are analyzed with the new model.•Their binding thermodynamics are consistently determined by global ana...

Full description

Saved in:
Bibliographic Details
Published in:Thermochimica acta 2013-07, Vol.563, p.82-89
Main Authors: Nakamura, Shigeyoshi, Koga, Shuntaro, Shibuya, Noriaki, Seo, Kazusa, Kidokoro, Shun-ichi
Format: Article
Language:eng ; dut
Subjects:
adenosine
Adenosine 5′-triphosphate
adenosine triphosphate
Adenosines
Binding
Bonding strength
calorimetry
cations
Constants
energy
Energy use
enthalpy
Enthalpy change
Fittings
Gibbs free energy change
heat
Isothermal titration calorimetry
Magnesium
Magnesium ion
potassium chloride
temperature
titration
Titration calorimetry
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:An illustration of the interaction model between adenosine 5′-triphosphate and magnesium ion. •We develop a new multi-binding model including Mg2ATP, and Mg(ATP)2.•The ITC data of ATP-Mg2+ binding are analyzed with the new model.•Their binding thermodynamics are consistently determined by global analysis. Adenosine 5′-triphosphate, ATP, is used as the molecular currency of energy in living systems, where divalent ions are bond to ATP strongly and ATP interacts with the protein through the cation in many cases. Therefore, the thermodynamic evaluation of the interaction between ATP and divalent cations is important to understand the biological function of ATP molecules. In this study, the interaction of ATP and Mg ion at pH 8.5 with 300mM KCl was evaluated by isothermal titration calorimetry. The temperature and ATP concentration dependence of the binding heat were analyzed by the global fitting with a new multi-binding model including ATP, MgATP, Mg2ATP, and Mg(ATP)2 state for ATP molecules. The binding constant and the binding enthalpy of ATP to MgATP at 25°C were determined to be 15M−1 and 10kJmol−1, respectively.
ISSN:0040-6031
1872-762X
DOI:10.1016/j.tca.2013.04.008