Measurement of solvation responses at multiple sites in a globular protein.

摘要: Proteins respond to electrostatic perturbations through complex reorganizations of their charged and polar groups, as well those the surrounding media. These solvation responses occur both in protein interior on its surface, though exact mechanisms are not understood, part because limited data for any given protein. Here, we characterize kinetics at sites throughout sequence a small globular protein, B1 domain streptococcal G (GB1), using synthetic fluorescent amino acid Aladan. Aladan was incorporated into seven different GB1 sites, time-dependent Stokes shift measured over femtosecond nanosecond time scales by fluorescence upconversion time-correlated single photon counting. The range from buried within core fully solvent-exposed located secondary structures including β-sheets, helices, loop...