Related Experiment Video
Updated: Jun 22, 2026

Application of I TASSER, trRosetta, UCSF Chimera, HADDOCK server, and HEX loria for De Novo and In Silico Design of Proteins
Published on: July 8, 2025
Comparative PCET study of a donor-acceptor pair linked by ionized and nonionized asymmetric hydrogen-bonded
Elizabeth R Young1, Joel Rosenthal, Justin M Hodgkiss
1Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA.
Abstract:
A Zn(II) amidinium porphyrin is the excited-state electron donor (D) to a naphthalene diimide acceptor (A) appended with either a carboxylate or sulfonate functionality. The two-point hydrogen bond (...[H(+)]...) formed between the amidinium and carboxylate or sulfonate functionalities establishes a proton-coupled electron transfer (PCET) pathway for charge transfer. The two D...[H(+)]...A assemblies differ only by the proton configuration within the hydrogen-bonding interface. Specifically, the amidinium ion transfers a proton to the carboxylate to form a nonionized amidine-carboxylic acid two-point hydrogen network, whereas the amidinium retains both protons when bound to the sulfonate functionality, forming an ionized amidinium-sulfonate two-point hydrogen bond network. These two interface configurations within the dyads thus allow for a direct comparison of the PCET kinetics for the same donor and acceptor juxtaposed by ionized and nonionized hydrogen-bonded interfaces. Analysis of the PCET kinetics ascertained from transient absorption and transient emission spectroscopy reveals that the ionized interface is more strongly impacted by the local solvent environment, thus establishing that the initial static configuration of the proton interface is a critical determinant in the kinetics of PCET.
More Related Videos
05:51Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
07:54Analysis of AtHIRD11 Intrinsic Disorder and Binding Towards Metal Ions by Capillary Gel Electrophoresis and Affinity Capillary Electrophoresis
Published on: August 22, 2018
Related Concept Videos
Complexation Equilibria: The Chelate Effect
Pore Transport and Ion-Pair Transport
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...
Protein-protein Interfaces
Ion Exchange
Ligand Binding and Linkage
Ionic Association