Membrane Proteins Have Distinct Fast Internal Motion and Residual Conformational Entropy. Academic Article uri icon


  • The internal motions of integral membrane proteins have largely eluded comprehensive experimental characterization. Here the fast side-chain dynamics of the -helical sensory rhodopsinII and the -barrel outer membrane proteinW have been investigated in lipid bilayers and detergent micelles by solution NMR relaxation techniques. Despite their differing topologies, both proteins have a similar distribution of methyl-bearing side-chain motion that is largely independent of membrane mimetic. The methyl-bearing side chains of both proteins are, on average, more dynamic in the ps-ns timescale than any soluble protein characterized to date. Accordingly, both proteins retain an extraordinary residual conformational entropy in the folded state, which provides a counterbalance to the absence of the hydrophobic effect. Furthermore, the high conformational entropy could greatly influence the thermodynamics underlying membrane-protein functions, including ligand binding, allostery, and signaling.

published proceedings

  • Angew Chem Int Ed Engl

altmetric score

  • 11.45

author list (cited authors)

  • O'Brien, E. S., Fuglestad, B., Lessen, H. J., Stetz, M. A., Lin, D. W., Marques, B. S., ... Wand, A. J.

citation count

  • 15

complete list of authors

  • O'Brien, Evan S||Fuglestad, Brian||Lessen, Henry J||Stetz, Matthew A||Lin, Danny W||Marques, Bryan S||Gupta, Kushol||Fleming, Karen G||Wand, A Joshua

publication date

  • June 2020