Radioactive sodium sulfate was fed to a cow, milk was collwted for several days, and the proteins were isolated. The proteins showed apprmeciable radioactivity. From the hydrolysate of the radioactive proteins cystine and methionine were separeated on chromatograms, and eluted. Both cystine and methionine contained radioactive sulfur in appreciable amounts.
No takes yet. Share an insight, caveat, or question.
Block et al. (1950) studied this question.