Probing Nonadiabaticity of Proton-Coupled Electron Transfer in Ribonucleotide Reductase.

J Phys Chem Lett

Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.

Published: February 2024

The enzyme ribonucleotide reductase, which is essential for DNA synthesis, initiates the conversion of ribonucleotides to deoxyribonucleotides via radical transfer over a 32 Å pathway composed of proton-coupled electron transfer (PCET) reactions. Previously, the first three PCET reactions in the α subunit were investigated with hybrid quantum mechanical/molecular mechanical (QM/MM) free energy simulations. Herein, the fourth PCET reaction in this subunit between C439 and guanosine diphosphate (GDP) is simulated and found to be slightly exoergic with a relatively high free energy barrier. To further elucidate the mechanisms of all four PCET reactions, we analyzed the vibronic and electron-proton nonadiabaticities. This analysis suggests that interfacial PCET between Y356 and Y731 is vibronically and electronically nonadiabatic, whereas PCET between Y731 and Y730 and between C439 and GDP is fully adiabatic and PCET between Y730 and C439 is in the intermediate regime. These insights provide guidance for selecting suitable rate constant expressions for these PCET reactions.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11586673PMC
http://dx.doi.org/10.1021/acs.jpclett.3c03552DOI Listing

Publication Analysis

Top Keywords

pcet reactions
16
proton-coupled electron
8
electron transfer
8
ribonucleotide reductase
8
pcet
8
free energy
8
y730 c439
8
probing nonadiabaticity
4
nonadiabaticity proton-coupled
4
transfer ribonucleotide
4

Similar Publications

Constructing an Isopolymolybdate-Based Bifunctional Photocatalyst for Promoting Nitroaromatic Reduction and C-H Oxidation.

Inorg Chem

December 2024

Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P. R. China.

Amide compounds are widely present in drug molecules and natural products, which can be synthesized by acid-amine condensation. It is urgent to design new photocatalysts for achieving both nitroaromatic reduction and C-H oxidation to obtain raw materials, carboxylic acids, and aromatic amines. Herein, a novel isopolymolybdate-incorporated photoactive metal-organic framework, -TPT, was constructed by combining the oxidation catalyst [MoO], Ni(II) cation, and photosensitive ligand 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT).

View Article and Find Full Text PDF

The electrochemical nitrate reduction reaction (NORR) involves multiple hydrogenation and deoxygenation steps, which compete with the hydrogen evolution reaction (HER). Therefore, NORR driven in acidic media is challenging in spite of advantageous fast hydrogen transfers in its elementary steps. The findings presented in this article first demonstrate that the NORR is significantly activated even in acidic lithium nitrate solutions at LiNO concentrations exceeding 6 m on a Pt electrode (the highly effective catalyst for HER) by the formation of a "hydronium-in-salt" electrolyte (HISE), a new type of aqueous high concentration salt electrolyte.

View Article and Find Full Text PDF

Diversified Fluoroalkylation of Alkenes Using Quaternary Fluoroalkyl Alcohols as the Fluoroalkylating Reagents.

Adv Sci (Weinh)

December 2024

Shanghai Frontiers Science Center of Drug Target Identification and Delivery, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai, 200240, China.

Given the widespread presence of fluoroalkyl functionalities in bioactive molecules, the development of fluoroalkylation reactions with bench-stable and easy-to-use fluoroalkylating reagents is highly desirable. In addition, realization of mono-, di-, tri-, or polyfluoroalkyation usually requires distinct types of fluoroalkylating reagents under different or even harsh reaction conditions, and a universal method to accomplish different hydrofluoroalkylation of alkenes is lacking. Herein, the use of quaternary fluoroalkyl alcohols is reported as the universal fluoroalkylating reagents to readily facilitate mono-, di-, tri-, or polyfluoroalkylation of a wide range of alkene substrates in high yields.

View Article and Find Full Text PDF

We report the proton-coupled electron transfer (PCET) reactivity of an octahedral Ta(V) aniline complex supported by an acridane-derived redox active NNN pincer ligand. The reversible binding of aniline to a Ta(V) dichloride induces significant coordination-induced bond weakening (CIBW) of the aniline N-H bonds. This enables a rare two-fold hydrogen atom abstraction, resulting in a terminal imido complex and a two-electron oxidation of the NNN pincer ligand, all while maintaining the metal's oxidation state.

View Article and Find Full Text PDF

CRYSTAL-SIZE-DEPENDENT OPTICAL PROPERTIES OF H-ATOMS ON THE NODES OF TI-BASED METAL-ORGANIC FRAMEWORK.

Chem Asian J

December 2024

University of Oklahoma, Chemistry and Biochemistry, 101 Stephenson Pkwy, Room 3310, 73019, Norman, UNITED STATES OF AMERICA.

Proton-coupled electron transfer (PCET) reactions are fundamental to energy storage and conversion processes. By coupling electrons with protons, the net charge neutrality is retained, preventing electrode decomposition due to charge imbalance. PCET reactions with equimolar amounts of protons and electrons can be considered as a net H-atom transfer (HAT) reaction.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!