Quantifying the Initial Unfolding of Bacteriorhodopsin Reveals Retinal Stabilization Journal Article uri icon



  • AbstractThe forces that stabilize membrane proteins remain elusive to precise quantification. Particularly important, but poorly resolved, are the forces present during the initial unfolding of a membrane protein, where the most native set of interactions is present. A high‐precision, atomic force microscopy assay was developed to study the initial unfolding of bacteriorhodopsin. A rapid near‐equilibrium folding between the first three unfolding states was discovered, the two transitions corresponded to the unfolding of five and three amino acids, respectively, when using a cantilever optimized for 2 μs resolution. The third of these states was retinal‐stabilized and previously undetected, despite being the most mechanically stable state in the whole unfolding pathway, supporting 150 pN for more than 1 min. This ability to measure the dynamics of the initial unfolding of bacteriorhodopsin provides a platform for quantifying the energetics of membrane proteins under native‐like conditions.

publication date

  • February 4, 2019

Date in CU Experts

  • November 17, 2020 9:34 AM

Full Author List

  • Yu H; Heenan PR; Edwards DT; Uyetake L; Perkins TT

author count

  • 5

Other Profiles

International Standard Serial Number (ISSN)

  • 0044-8249

Electronic International Standard Serial Number (EISSN)

  • 1521-3757

Additional Document Info

start page

  • 1724

end page

  • 1727


  • 131


  • 6