Article ID Journal Published Year Pages File Type
1987679 International Journal of Biological Macromolecules 2010 10 Pages PDF
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 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.

Related Topics
Life Sciences Biochemistry, Genetics and Molecular Biology Biochemistry
Authors
, , , , , , , , , ,