Efficient incorporation of deuterated amino acids into quail egg white proteins for nuclear magnetic resonance studies

The in vivo incorporation of deuterated amino acids into egg white proteins of Japanese quail is described. Using a synthetic diet, the level of incorporation of selectively deuterated tyrosine, tryptophan, histidine, and phenylalanine into lysozyme was greater than 80% as demonstrated by proton NMR. Load and load-chase experiments using [3H]phenylalanine or [3H]leucine monitored the fast uptake time (t sub 1/2 = 2 days) and confirmed the high levels of incorporation. The potential of this system for preparation of other proteins for NMR spectroscopy is discussed