phenylalanine hydroxylase
Quick Summary
Phenylalanine hydroxylase (PAH) is an enzyme crucial for metabolizing the amino acid phenylalanine. In a healthy body, PAH converts phenylalanine into tyrosine. However, in individuals with the genetic disorder phenylketonuria (PKU), this enzyme is inactive.1
This inactivity leads to a buildup of phenylalanine in the blood and other bodily fluids. Excess phenylalanine and its byproducts can harm the central nervous system, potentially causing intellectual disability, seizures, and developmental issues. It can also affect melanin production, leading to lighter skin, hair, and eye color. PKU is an autosomal recessive inherited disorder, meaning it's passed down through genes. Early detection and a diet low in phenylalanine are key to managing the condition.12
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phenylketonuria…organic catalyst, or enzyme, called phenylalanine hydroxylase. This enzyme is not active in individuals who have phenylketonuria. As a result of this metabolic block, abnormally high levels of phenylalanine accumulate in the blood, cerebrospinal fluid, and urine. Abnormal products of phenylalanine breakdown, such as highly reactive ketone compounds, can also…
Read More…organic catalyst, or enzyme, called phenylalanine hydroxylase. This enzyme is not active in individuals who have phenylketonuria. As a result of this metabolic block, abnormally high levels of phenylalanine accumulate in the blood, cerebrospinal fluid, and urine. Abnormal products of phenylalanine breakdown, such as highly reactive ketone compounds, can also…
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human genetic diseaseAutosomal recessive inheritance…the gene encoding the enzyme phenylalanine hydroxylase (PAH). PAH normally catalyzes the conversion of phenylalanine, an amino acid prevalent in dietary proteins and in the artificial sweetener aspartame, to another amino acid called tyrosine. In persons with PKU, dietary phenylalanine either accumulates in the body or some of it is…
Read More…the gene encoding the enzyme phenylalanine hydroxylase (PAH). PAH normally catalyzes the conversion of phenylalanine, an amino acid prevalent in dietary proteins and in the artificial sweetener aspartame, to another amino acid called tyrosine. In persons with PKU, dietary phenylalanine either accumulates in the body or some of it is…
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metabolic diseaseDisorders of amino acid metabolism…caused by decreased activity of phenylalanine hydroxylase (PAH), an enzyme that converts the amino acid phenylalanine to tyrosine, a precursor of several important hormones and skin, hair, and eye pigments. Decreased PAH activity results in accumulation of phenylalanine and a decreased amount of tyrosine and other metabolites. Persistent high levels…
Read More…caused by decreased activity of phenylalanine hydroxylase (PAH), an enzyme that converts the amino acid phenylalanine to tyrosine, a precursor of several important hormones and skin, hair, and eye pigments. Decreased PAH activity results in accumulation of phenylalanine and a decreased amount of tyrosine and other metabolites. Persistent high levels…
Read More