Stability of a Nonequilibrium Biochemical Cycle Revealed by Single-Molecule Spectroscopy
Talele, S.; King, J. T.
Show abstract
Biological machinery relies on nonequilibrium dynamics to maintain stable directional fluxes through complex reaction cycles. For such reaction cycles, the presence of microscopically irreversible conformational transitions of the protein, and the accompanying entropy production, is of central interest. In this work, we use multidimensional single-molecule fluorescence lifetime correlation spectroscopy to measure the forward and reverse conformational transitions of bacteriorhodopsin during trans-membrane H+ pumping. We quantify the flux, affinity, enthalpy and entropy production through portions of the reaction cycle as a function of temperature. We find that affinity of irreversible conformational transitions decreases with increasing temperature, resulting in diminishing flux and entropy production. We show that the temperature dependence of the transition affinity is well fit by the Gibbs-Helmholtz relation, allowing the {Delta}Htrans to be experimentally extracted.
Matching journals
The top 4 journals account for 50% of the predicted probability mass.
Similar papers in this journal
- Environmental dipolar relaxation during excited state proton transfer in Green Fluorescent Protein 93%
- Slow conformational changes of blue light sensor BLUF proteins in milliseconds 93%
- Water inside the selectivity filter of a K+ ion channel: structural heterogeneity, picosecond dynamics, and hydrogen-bonding 93%
Similar papers in this journal
- Substrates modulate charge-reorganization allosteric effects in protein-protein association 93%
- mEos4b photoconversion efficiency depends on laser illumination conditions used in PALM 92%
- High efficiency excitation energy transfer in biohybrid quantum dot-bacterial reaction center nanoconjugates 92%
Similar papers in this journal
Similar papers in this journal
- Identification of residues potentially involved in optical shifts in the water-soluble chlorophyll-a binding protein through molecular dynamics simulations 92%
- Kinetic Insights into Photoinduced Monomer-Dimer Conversion and Activation of Orange Carotenoid Protein 92%
- Intrinsically disordered proteins can behave as different polymers across their conformational ensemble 92%
Similar papers in this journal
"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.