# Conformational Landscape of NADH and Ion Binding in Water/DMSO Mixtures via 31P NMR Spectroscopy

## TL;DR

This study explores how NADH's structure changes in water/DMSO mixtures and how ions affect these changes using NMR techniques.

## Contribution

The study provides new insights into NADH conformational behavior and ion binding in mixed solvents using 31P NMR methods.

## Key findings

- NADH shows conformational changes influenced by solvent composition and ion binding.
- 31P NMR relaxation and CEST experiments reveal solvent-dependent structural flexibility.
- Findings align with molecular dynamics simulations and highlight the solvent's role in NADH behavior.

## Abstract

This study reports on the conformational states of nicotinamide
adenine dinucleotide (NADH) in water/DMSO mixtures and examines the
influence of ion binding. We observe evidence of conformational changes
through a series of NMR techniques, including 31P NMR relaxation
(R1 and R2), chemical exchange saturation transfer (CEST), and diffusion-ordered
spectroscopy (DOSY) experiments. The observed variation of the conformational
states is indicative of the solvent’s influence on NADH’s
structural flexibility. The experimental findings, in combination
with viscosity data, are shown to be in line with findings from earlier
molecular dynamics studies. The reported observations emphasize the
critical role of the solvent environment in determining the conformational
states of NADH and similar molecules with relevance for the biophysiological
context. The results found herein can help in studying the biophysical
behavior of NADH and similar biomolecules and their associated metabolic
pathways under various solvent conditions.