NMR detection and conformational dependence of two, three, and four-bond isotope shifts due to deuteration of backbone amides.

ABSTRACT: NMR isotope shifts occur due to small differences in nuclear shielding when nearby atoms are different isotopes. For molecules dissolved in 1:1 H₂O:D₂O, the resulting mixture of N-H and N-D isotopes leads to a small splitting of resonances from adjacent nuclei. We used multidimensional NMR to measure isotope shifts for the proteins CUS-3iD and CspA. We observed four-bond ⁴∆N(ND) isotope shifts in high-resolution 2D ¹⁵N-TROSY experiments of the perdeuterated proteins that correlate with the torsional angle psi. Three-bond ³∆C'(ND) isotope shifts detected in H(N)CO spectra correlate with the intraresidue H-O distance, and to a lesser extent with the dihedral angle phi. The conformational dependence of the isotope shifts agree with those

SUBMITTER: Alexandrescu AT 

PROVIDER: S-EPMC10724557 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature