High resolution ¹³C-detected solid-state NMR spectroscopy of a deuterated protein

High resolution ¹³C-detected solid-state NMR spectra of the deuterated beta-1 immunoglobulin binding domain of the protein G (GB1) have been collected to show that all ¹⁵N, ¹³C', C¹³Cα and ¹³Cβ sites are resolved in C¹³C-¹³C and ¹⁵N-C¹³C spectra, with significant improvement in T(2) relaxation times and resolution at high magnetic field (750 MHz). The comparison of echo T(2) values between deuterated and protonated GB1 at various spinning rates and under different decoupling schemes indicates that ¹³Cα T(2)' times increase by almost a factor of two upon deuteration at all spinning rates and under moderate decoupling strength, and thus the deuteration enables application of scalar-based correlation experiments that are challenging from the standpoint of transverse relaxation, with moderate proton decoupling. Additionally, deuteration in large proteins is a useful strategy to selectively detect polar residues that are often important for protein function and protein-protein interactions.