Specific interactions of C-terminal half (C-lobe) of lactoferrin protein with edible sugars: binding and structural studies with implications on diabetes.Mir, R., Kumar, R.P., Singh, N., Vikram, G.P., Sinha, M., Bhushan, A., Kaur, P., Srinivasan, A., Sharma, S., Singh, T.P.
(2010) Int J Biol Macromol 47: 50-59
- PubMed: 20371371
- DOI: 10.1016/j.ijbiomac.2010.03.021
- Structures With Same Primary Citation
- PubMed Abstract:
Bovine lactoferrin has been shown to reduce the levels of glucose in both normal subjects and non-insulin dependent diabetic patients. The binding studies have shown that various sugar molecules interact with lactoferrin indicating the presence of a ...
Bovine lactoferrin has been shown to reduce the levels of glucose in both normal subjects and non-insulin dependent diabetic patients. The binding studies have shown that various sugar molecules interact with lactoferrin indicating the presence of a sugar-binding site in the protein. Structural studies have revealed that the sugar-binding site is located in the C-terminal half (C-lobe) of bilobal lactoferrin. Since the sugar-binding site was part of the C-lobe, it was better to carry out binding and structural studies using C-lobe rather than the full protein molecule. Therefore, C-lobe was prepared by limited proteolysis of lactoferrin with enzyme proteinase K. It was purified to homogeneity for further studies. The addition of C-lobe to human serum showed significant lowering of glucose levels. The binding studies using C-lobe with nine sugars, glucose, galactose, mannose, xylose, maltose, cellobiose, lactose, sucrose and dextrin gave values of binding constants in the range of 10(-4) to 10(-5)M. The structure determinations of the complexes of C-lobe with all the nine sugars showed that all of them interact with C-lobe through the same recognition site involving several hydrogen bonds and van der Waals interactions.
Department of Biophysics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India.