NMR-based Analysis Of Bound Metabolites In Human Blood Serum

It was found that many metabolites are fully or partially bound to serum proteins in blood. Generally, the metabolites with high binding affinity are undetectable with conventional NMR approaches, because of their broad NMR lineshape and low sensitivity associated with the bound form. In this thesis, NMR experiment based on saturation transfer difference (STD) and WaterLOGSY (water-ligand observed via gradient spectroscopy) has been used to detect the bound metabolites in human blood plasma. The main content is as follows:1. The bounded metabolites which are fully or partially bound to the serum proteins in blood serum can be selectively detected using STD or WaterLOGSY technologies. Many metabolites have been found binding to the macromolecules in serum, such as lactate, isoleucine, alanine, glutamine, glutamate, acetoacetate, lysine, glucose, 1(3)-methyl-histidine, tyrosine, phenylalanine, etc. The binding site and the binding affinity have also been analysis thereafter. It indicated that lactate have relatively lower affinity to lipoprotein, because of it's small NOE transfer rates. This explained that why lactate released upon adding IBP to serum. 2. STD experiment was applied to detect bounded metabolites in two different groups, normal and hyperlipidemia. Though the signal to noise ratios of the experiments is relatively lower, it can be used to distinguish two different groups, because it can selectively detect the lipoprotein and its bounded metabolites. The results are consistent with the conventional clinical plasma chemistry results.