biostudies-literatureKrishnarjuna BNational Institute of HealthNCI NIH HHSNIGMS NIH HHS1628https://www.ebi.ac.uk/biostudies/studies/S-EPMC9687133biostudies-literatureUnknown12(11)Residual dipolar couplings (RDCs) are increasingly used for high-throughput NMR-based structural studies and to provide long-range angular constraints to validate and refine structures of various molecules determined by X-ray crystallography and NMR spectroscopy. RDCs of a given molecule can be measured in an anisotropic environment that aligns in an external magnetic field. Here, we demonstrate the first application of polymer-based nanodiscs for the measurement of RDCs from nucleic acids. Polymer-based nanodiscs prepared using negatively charged SMA-EA polymer and zwitterionic DMPC lipids were characterized by size-exclusion chromatography, ¹H NMR, dynamic light-scattering, and ²H NMR. The magnetically aligned polymer-nanodiscs were used as an alignment medium to measure RDCs from a ¹³C/¹⁵N-labeled fluoride riboswitch aptamer using 2D ARTSY-HSQC NMR experiments. The results showed that the alignment of nanodiscs is stable for nucleic acids and nanodisc-induced RDCs fit well with the previously determined solution structure of the riboswitch. These results demonstrate that SMA-EA-based lipid-nanodiscs can be used as a stable alignment medium for high-resolution structural and dynamical studies of nucleic acids, and they can also be applicable to study various other biomolecules and small molecules in general.BiomoleculesPolymer-Nanodiscs as a Novel Alignment Medium for High-Resolution NMR-Based Structural Studies of Nucleic Acids.PMC9687133R24GM141526R24 GM141526R01 GM114432R35GM139573R01GM114432P30 CA016086R35 GM139573Krishnarjuna BFaison EMTonelli MRavula TZhang QRamamoorthy AfalsePolymer-Nanodiscs as a Novel Alignment Medium for High-Resolution NMR-Based Structural Studies of Nucleic Acids.Residual dipolar couplings (RDCs) are increasingly used for high-throughput NMR-based structural studies and to provide long-range angular constraints to validate and refine structures of various molecules determined by X-ray crystallography and NMR spectroscopy. RDCs of a given molecule can be measured in an anisotropic environment that aligns in an external magnetic field. Here, we demonstrate the first application of polymer-based nanodiscs for the measurement of RDCs from nucleic acids. Polymer-based nanodiscs prepared using negatively charged SMA-EA polymer and zwitterionic DMPC lipids were characterized by size-exclusion chromatography, ¹H NMR, dynamic light-scattering, and ²H NMR. The magnetically aligned polymer-nanodiscs were used as an alignment medium to measure RDCs from a ¹³C/¹⁵N-labeled fluoride riboswitch aptamer using 2D ARTSY-HSQC NMR experiments. The results showed that the alignment of nanodiscs is stable for nucleic acids and nanodisc-induced RDCs fit well with the previously determined solution structure of the riboswitch. These results demonstrate that SMA-EA-based lipid-nanodiscs can be used as a stable alignment medium for high-resolution structural and dynamical studies of nucleic acids, and they can also be applicable to study various other biomolecules and small molecules in general.2022-01-01T00:00:00Z2022 Nov2026-05-08T03:11:22.189Z2025-04-21T14:15:37.685ZS-EPMC96871333635898310.3390/biom12111628