can be used to monitor conformational changes in proteins as they relate to protein function. If conformation is altered as result of post-translational modification, enzyme activation, drug binding or other functional events, there will likely be a change to H/D exchange that can be detected. HDXsite online webserver HDXsite is an online websever which includes some applications such as HDX modeller increasing the resolution of experimental HDX data and modeling protection factors for individual residues. References Further reading Chemical reactions Protein structure Spectroscopy Mass spectrometry