Medical Definition of Tyrosine
Tyrosine: An amino acid, one of the 20 building blocks of protein. A nonessential amino acid, tyrosine is produced from another amino acid, phenylalanine. Deficiency of the enzyme phenylalanine hydroxylase that catalyzes this reaction causes the genetic disease called phenylketonuria (PKU). Tyrosine is a precursor of thyroid hormones, catecholamines, and melanin. Symbol: Tyr.Source: MedTerms™ Medical Dictionary
Last Editorial Review: 6/9/2016
Medical Dictionary Definitions A - Z
Search Medical Dictionary
- Personalized Tips for Managing Migraine
- Do You Take Good Care of Your Eyes?
- Tips for a Clean Home & Healthy Cat