Conformational flexibility of avidin: the influence of biotin binding.
Ligand binding to proteins is a key process in cell biochemistry. The interaction usually induces modifications in the unfolding thermodynamic parameters of the macromolecule due to the coupling of unfolding and binding equilibria. In addition, these modifications can be attended by changes in protein structure and/or conformational flexibility induced by ligand binding. In this work, we have explored the effect of biotin binding on conformation and dynamic properties of avidin by using infrared spectroscopy including kinetics of hydrogen/deuterium exchange. Our results, along with previously thermodynamic published data, indicate a clear correlation between thermostability and protein compactness. In addition, our results also help to interpret the thermodynamic binding parameters of the exceptionally stable biotin:AVD complex.
Celej
M Soledad
MS
Centro de Investigaciones en Química Biológica de Córdoba-CIQUIBIC, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
Montich
Guillermo G
GG
Fidelio
Gerardo D
GD
D001360:Avidin / Q000737:chemistry*; D001665:Binding Sites; D001710:Biotin / Q000737:chemistry*; D041961:Deuterium Exchange Measurement; D046912:Multiprotein Complexes / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D013055:Spectrophotometry, Infrared; D013329:Structure-Activity Relationship
D046912:Multiprotein Complexes; D001360:Avidin; D001710:Biotin