Using Isothermal Titration Calorimetry to Determine Thermodynamic Parameters of Protein–Glycosaminoglycan Interactions

  • Amit K. Dutta
  • Jörg Rösgen
  • Krishna RajarathnamEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1229)


It has now become increasingly clear that a complete atomic description of how biomacromolecules recognize each other requires knowledge not only of the structures of the complexes but also of how kinetics and thermodynamics drive the binding process. In particular, such knowledge is lacking for protein–glycosaminoglycan (GAG) complexes. Isothermal titration calorimetry (ITC) is the only technique that can provide various thermodynamic parameters—enthalpy, entropy, free energy (binding constant), and stoichiometry—from a single experiment. Here we describe different factors that must be taken into consideration in carrying out ITC titrations to obtain meaningful thermodynamic data of protein–GAG interactions.

Key words

Glycosaminoglycan (GAG) Heparin Free energy Thermodynamics Isothermal titration calorimetry (ITC) Enthalpy Entropy 



This work was supported in part by grants P01HL1071521 and R21AI097975 to K.R. and R01GM049760 to J.R. from the National Institutes of Health. The authors would like to thank Dr. Luis Holthauzen for technical support.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Amit K. Dutta
    • 1
  • Jörg Rösgen
    • 2
  • Krishna Rajarathnam
    • 1
    • 3
    Email author
  1. 1.Department of Biochemistry and Molecular BiologyThe University of Texas Medical BranchGalvestonUSA
  2. 2.Department of Biochemistry and Molecular BiologyPenn State College of MedicineHersheyUSA
  3. 3.Sealy Center for Structural Biology and Molecular BiophysicsThe University of Texas Medical BranchGalvestonUSA

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