One thing is the proton affinity of an amino-acid residue when the amino acid is dissolved in a lot of water in, say, a glass beaker; another thing is the affinity for protons in the complex microenvironment presented by a membrane protein. For the first time, we were able to measure proton-transfer events at the single-proton, single-amino-acid level, in real time. Chemists will be happy to see this. |
Our paper has implications that are specific to this receptor, but many of the findings can be extended to several other membrane proteins. |
We are working with the open state of the ion channel, and we now know how the helices that line the pore are oriented. This was not known before. Previous work has told us how the helices are oriented in the closed state. |