Protein deuteration via algal amino acids to overcome proton back-exchange for fast-MAS solid-state NMR of large proteins

With perdeuteration, a current standard for solid-state NMR spectroscopy, large proteins suffer from incomplete amide-proton back-exchange. Using a 72 kDa micro-crystalline protein, we show that deuteration exclusively via deuterated amino acids, largely suppressing sidechain protonation, provides spectral resolution comparable to perdeuterated preparations at intermediate spinning frequencies without proton back-exchange obstacles.