Comparison of the sensitivities of WaterLOGSY and saturation transfer difference NMR experiments
Abstract
The WaterLOGSY (WL) and saturation transfer difference (STD) NMR experiments have proven to be extremely useful techniques to characterize interactions between small molecules and large biomolecules. In this work we compare the relative sensitivities of WL and STD NMR using 3 experimental systems: ketoprofen (KET)â??bovine serum albumin (BSA),
tert-butyl hydroquinone (TBHQ)â??hemagglutinin (HA), and chloramphenicol (CAM)â??ribosome (70S). In all cases we find that WL is more sensitive than STD for a given experimental time with the ratios ranging from 3.2 for KETâ??BSA to 16 for TBHQâ??HA and CAMâ??70S. We attribute the increased sensitivity of WL to be due to simultaneous saturation of multiple sources of cross correlation, including direct NOEs of 1H of water and exchangeable groups and indirect NOEs of 1Hâ??C groups. We suggest that the outstanding sensitivity of WL make it ideally suited for drug screening efforts targeting very large biomolecules at relatively low concentrations.
Source: Journal of Biomolecular NMR