hi, I am looking for a way to tell the state of the G protein I am working with. you know G proteins are found in GTP or GDP bound states. I need a way to tell between these two. I am loading my protein with GTP the way they do in the literature. but I want to have an idea of what percent of my protein is actually in the state I want. does anybody have an idea? thanks in advance.
confirming nucleotide state of isolated G protein
1 reply to this topic
Posted 06 February 2009 - 06:52 AM
Use radiolabelled GTP. You can calculate from specific activity the mols of protein that are GTP bound and then you can also calculate the hydrolysis by loss of counts. I also saw that perkin elmer has a system for fluorescent detection rather than radioactive. I'm sure if you do a literature search you will find groups who have done exactly what you are hoping to accomplish. You can then look at the protocols they publish or reference.