P-hydroxyphenylpyruvate

The tyrosine in the human body comes from the hydroxylation reaction of food and phenylalanine in the body, and then undergoes catabolism through different pathways. A small portion of tyrosine is metabolized to dopa. It is further changed into dopamine, norepinephrine, and epinephrine; most of the decomposition of tyrosine is converted to uric acid, which is further broken down into acetoacetic acid and fumaric acid, a rare genetic p-hydroxyphenylpyruvate oxidase or uric acid Enzyme deficiency results in tyrosinemia and black urine. During tyrosinemia, p-hydroxyphenylpyruvate and the like increase in urine, which can have severe liver damage, and children often die during infancy.