Which of the following is elevated in Pyridoxal Phosphate deficiency?
Xanthurenic acid >> Homocysteine (Both are increased in PLP deficiency) 3-OH Kynurenine is one of the intermediate in Tryptophan catabolism Normally conveed to next intermediate and this conversion requires vitamin B6/ PLP. But in B6 deficiency, 3-OH Kynurenine is diveed to form alternate metabolite= Xanthurenic acid (See fig) which is excreted in urine. Homocystine is a chemical compound consisting of two homocysteine molecules joined by a disulfide.
FIGLU
Homocystine
Methylmalonic acid
Xanthurenic acid
Classification and metabolism of amino acids