Determination and significance of l-tyrosine O-sulphate and its deaminated metabolites in normal human and mouse urine

Methods were developed for the determination of the O-sulphate esters of l-tyrosine, p-hydroxyphenylpyruvate, p-hydroxyphenylacetate and p-hydroxybenzaldehyde in human urine. The amounts of these esters normally present in human female urine were determined. The quantities and specific radioactivities of l-tyrosine O-sulphate and p-hydroxyphenylpyruvate O-sulphate in mouse urine after labelled tyrosine had been fed were determined and were consistent with the hypothesis that the sole source of p-hydroxyphenylpyruvate O-sulphate was l-tyrosine O-sulphate. It is suggested that the turnover of known polypeptides containing l-tyrosine O-sulphate residues can account for only a portion of the quantities of the ester and its metabolite(s) that are present in normal female human urine.