Allostery plays a crucial role in the mechanism of neurotransmitter-sodium symporters, such as the human dopamine transporter. To investigate the molecular mechanism that couples the transport-associated inward release of the Na ion from the Na2 site to intracellular gating, we applied a combination of the thermodynamic coupling function (TCF) formalism and Markov state model analysis to a 50-μs data set of molecular dynamics trajectories of the human dopamine transporter, in which multiple spontaneous Na release events were observed. Our TCF approach reveals a complex landscape of thermodynamic coupling between Na release and inward-opening, and identifies diverse, yet well-defined roles for different Na-coordinating residues. In particular, we identify a prominent role in the allosteric coupling for the Na-coordinating residue D421, where mutation has previously been associated with neurological disorders. Our results highlight the power of the TCF analysis to elucidate the molecular mechanism of complex allosteric processes in large biomolecular systems.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5773750 | PMC |
http://dx.doi.org/10.1016/j.bpj.2017.10.030 | DOI Listing |
J Phys Chem Lett
December 2024
Department of Chemistry and Department of Physics, Westlake University, Hangzhou, Zhejiang 310030, China.
Collective strong light-matter coupling provides a versatile means to manipulate physicochemical properties of molecules and materials. Understanding collective polaritonic dynamics is hindered by the macroscopic number of molecules interacting collectively with photonic modes. We develop a many-body theory to investigate the spectroscopy and dynamics of a molecular ensemble embedded in an optical cavity in the collective strong coupling regime.
View Article and Find Full Text PDFAdv Mater
December 2024
International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Shaanxi, 710049, China.
The direct photocatalytic conversion of CO and HO into high-value C chemicals holds great promise but remains challenging due to the intrinsic difficulty of C-C and C-C coupling processes and the lack of clarity regarding the underlying reaction mechanisms. Here, the design and synthesis of a Cu-ZnS photocatalyst featuring dispersed Cu single atoms are reported. These Cu single atoms are coordinated with S atoms, forming unique Cu-S-Zn active units with tunable charge distributions that interact favorably with surface-adsorbed intermediates.
View Article and Find Full Text PDFInteractions between magma oceans and overlying atmospheres on young rocky planets leads to an evolving feedback of outgassing, greenhouse forcing, and mantle melt fraction. Previous studies have predominantly focused on the solidification of oxidized Earth-similar planets, but the diversity in mean density and irradiation observed in the low-mass exoplanet census motivate exploration of strongly varying geochemical scenarios. We aim to explore how variable redox properties alter the duration of magma ocean solidification, the equilibrium thermodynamic state, melt fraction of the mantle, and atmospheric composition.
View Article and Find Full Text PDFSheng Wu Gong Cheng Xue Bao
December 2024
The College of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China.
This study aims to optimize the process for preparing chitosan-based ultrasound-coupled hydrogel pads and investigate their application potential in ultrasonography. Chitosan, 2-acrylamido-2-methylpropanesulfonic acid, and N-isopropylacrylamide were used as the main materials to prepare chitosan-based ultrasound-coupled hydrogel pads. The free-radical polymerization conditions were optimized by a three-factor, three-level orthogonal test with the tensile strength and ultrasound image quality of the hydrogel pads as evaluation indicators.
View Article and Find Full Text PDFJ Am Chem Soc
December 2024
Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
Hydroalkylation of terminal alkynes is a powerful approach to the synthesis of disubstituted alkenes. However, its application is largely unexplored in the synthesis of α,β-unsaturated carbonyls, which are common among synthetic intermediates and biologically active molecules. The thermodynamically less stable -isomers of activated alkenes have been particularly challenging to access because of their propensity for isomerization and the paucity of reliable -selective hydroalkylation methods.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!