The solution is a description of the concept of applying fluorescence polarization to measure protein-peptide binding interactions.
Fluorescence polarization (sometimes called fluorescence anisotropy) is a spectroscopic method that can be exploited in order to measure binding interactions between a fluorescent low molecular weight entity (in this case, the fluorescein-labeled peptide) and a much larger molecular weight entity (in this case, the protein. The basis of using fluorescence polarization for this type of application is the difference in size. The small molecular weight peptide is small and compact, and so it rotates very quickly in solution. In contrast, the large protein is big and bulky, and rotates quite slowly in solution.
When polarized light is used to excite a sample containing the fluorescent peptide alone, the ...
Explain, in general terms/text, how fluorescence polarization could be used to measure the interaction between a fluorescein-labeled peptide and a protein known to bind to that protein.