Fenylalanín

Fenylalanín is an alpha-amino acid with the formula C9H11NO2. It is classified as an essential amino acid, meaning the human body cannot synthesize it and must obtain it from the diet. Fenylalanín has a hydrophobic side chain and plays a crucial role as a building block for proteins. It is also a precursor to several important biomolecules.

In the body, fenylalanín is converted into tyrosine, another amino acid, through enzymatic hydroxylation. Tyrosine, in turn, is a precursor for catecholamines such as dopamine, norepinephrine, and epinephrine, which are vital neurotransmitters and hormones. Additionally, tyrosine is used in the synthesis of melanin, the pigment responsible for skin, hair, and eye color, and thyroid hormones, which regulate metabolism.

Sources of fenylalanín in the diet include protein-rich foods such as meat, fish, eggs, dairy products, and legumes. Individuals with the genetic disorder phenylketonuria (PKU) are unable to metabolize fenylalanín properly. This leads to a buildup of fenylalanín in the body, which can cause severe intellectual disability and other health problems if left untreated. Dietary management, involving the restriction of fenylalanín intake, is essential for individuals with PKU. It is also a component of the artificial sweetener aspartame.