Due to excessive glycation, structure of protein may get altered, which results in abnormal functions of proteins. The glycation process can occur inside or outside of the body, whenever glucose molecules react with proteins. The impaired proteins are named as advanced glycation end products (AGEs). The AGEs are responsible for various diabetic complications and may lead to various diseases. AGEs can block the insulin receptors on cells and patient may develop insulin resistance. Glycation affects all cells, making it responsible for aging. Formation of unstable Schiff’s base is first step in glycation reaction followed by conversion of Schiff’s base into stable reversible Admori product in second step. Finally, AGEs are formed by further changes in Admori products by series of reactions of dehydration and fragmentation. Glycation reaction mainly occurs at amino group of lysine and arginine residues, as glycation process involves proteins, it becomes indispensable to study proteins. This study was carried out to know the positions of amino acids which are always accessible under different conformational changes, for smaller molecules like glucose. Due to which chances of glycation at specific positions increases where numbers of post translation modifications are possible. Various studies regarding the specific sites of glycation on human serum albumin are carried out all over the world but these studies were restricted to sites of crystal structure of human serum albumin alone or sites of glycated human serum albumin glycated with glucose and similar glycating agent. Due to conformational change of human serum albumin after binding of another ligand the positions of glycation changes because of this glycation pattern has direct relation with the structural conformation of protein. So, we have studied possible conformations of human serum albumin, The crystallographic structure of human serum albumin was obtained from the Protein Data Bank (PDB), a repository for the 3-D structural data of large biological molecules, such as proteins. We have analysed changes in accessible positions of lysine and arginine on HSA after under different conformational changes due to ligand binding. Finally, we have analysed the glycated sample of human serum albumin by liquid chromatography-mass spectrometry (LC-MS) to study post translation modifications on identified glycation prone lysine and arginine amino acid positions of human serum albumin.
