Phenylalanine

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Hello there, my question is why dont they make a meter for pku patciantes like they do for diabities...

Hi my name is jason, & I'am new at this

Phe redirects here. For the BitTorrent feature, see PHE

PHE

PHE may refer to* Paramount Home Entertainment* BitTorrent protocol encryption* Phenylalanine, a nonpolar amino acid with a hydrophobic side chain...
. For the constellation, see Phoenix (constellation)

Phoenix (constellation)

Phoenix is a minor constellation in the southern sky. It is named after the Phoenix , a mythical bird. It is faint; there are only two stars in the whole constellation which are brighter than magnitude 5.0....
.

Phenylalanine (abbreviated as Phe or F) is an a-amino acid

Amino acid

In chemistry, an amino acid is a molecule containing both amine and carboxyl functional groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent....
 with the formula

Chemical formula

A chemical formula is a way of expressing information about the atoms that constitute a particular chemical compound, and how the relationship between those atoms changes in chemical reactions....
 HO₂CCH(NH₂)CH₂C₆H₅, which is found naturally in the breast milk of mammals and manufactured for food and drink products and are also sold as nutritional supplements for their reputed analgesic

Analgesic

An analgesic is any member of the diverse group of Medication used to relieve pain . The word analgesic derives from Greek an- and algos ....
 and antidepressant

Antidepressant

An antidepressant is a psychiatric medication used for alleviating major depressive disorder or dysthymia. Drug groups known as MAOIs, tricyclics, and second-generation antidepressants such as SSRIs, and serotonin-norepinephrine reuptake inhibitors are particularly associated with the term....
 effects. Phenylalanine is structurally closely related to dopamine

Dopamine

Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the human brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors ? D1, D2, D3, D4 and D5, and their variants....
, epinepherine (adrenaline) and tyrosine

Tyrosine

Tyrosine or 4-hydroxyphenylalanine, is one of the 20 amino acids that are used by cell to protein biosynthesis proteins. This is a non-essential amino acid and it is found in casein....
.

This essential amino acid

Essential amino acid

File:BakedFish.jpgAn essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo synthesis by the organism , and therefore must be supplied in the diet....
 is classified as nonpolar because of the hydrophobic nature of the benzyl

Benzyl

In organic chemistry, benzyl is the term used to describe the substituent or molecular fragment possessing the structure C6H5CH2-....
 side chain. The codons for L-phenylalanine are UUU and UUC. It is a white, powdery solid

Solid

A solid object is in the states of matter characterized by resistance to deformation and changes of volume. In other words, it has high values both of Young's modulus and of shear modulus; this contrasts e.g....
. L-Phenylalanine (LPA) is an electrically-neutral amino acid

Amino acid

In chemistry, an amino acid is a molecule containing both amine and carboxyl functional groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent....
, one of the twenty common amino acids used to biochemically form protein

Protein

Proteins are organic compounds made of amino acids arranged in a linear chain and joined together by peptide bonds between the carboxyl and amino groups of adjacent amino acid Residue ....
s, coded for by DNA

DNA

Deoxyribonucleic acid is a nucleic acid that contains the genetics instructions used in the development and functioning of all known living organisms and some viruses....
.

Other biological roles

L-phenylalanine can also be converted into L-tyrosine

Tyrosine

Tyrosine or 4-hydroxyphenylalanine, is one of the 20 amino acids that are used by cell to protein biosynthesis proteins. This is a non-essential amino acid and it is found in casein....
, another one of the DNA-encoded amino acids. L-tyrosine in turn is converted into L-DOPA, which is further converted into dopamine

Dopamine

Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the human brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors ? D1, D2, D3, D4 and D5, and their variants....
, norepinephrine

Norepinephrine

Norepinephrine or noradrenaline is a catecholamine with dual roles as a hormone and a neurotransmitter.As a stress hormone, norepinephrine affects parts of the brain where attention and responding actions are controlled....
 (noradrenaline), and epinephrine

Epinephrine

Epinephrine is a hormone and neurotransmitter.Epinephrine increases the "fight or flight" response of the Sympathetic nervous system of the autonomic nervous system....
 (adrenaline). The latter three are known as the catecholamines.

Phenylalanine uses the same active transport channel as tryptophan

Tryptophan

Tryptophan is one of the 20 List of standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG....
 to cross the blood-brain barrier

Blood-brain barrier

The blood-brain barrier is a metabolic or cellular structure in the central nervous system that restricts the passage of various chemical substances and microscopic objects between the bloodstream and the neural tissue itself, while still allowing the passage of substances essential to metabolism function ....
, and, in large quantities, interferes with the production of serotonin

Serotonin

Serotonin is a monoamine neurotransmitter synthesized in serotonergic neurons in the central nervous system and enterochromaffin cells in the gastrointestinal tract of animals including humans....
.

Lignan

Lignan

The lignans are a group of chemical compounds found in plants, particularly in flax seed. Lignans are one of the major classes of phytoestrogens, which are estrogen-like chemicals and also act as antioxidants....
 is derived from phenylalanine and from tyrosine

Tyrosine

Tyrosine or 4-hydroxyphenylalanine, is one of the 20 amino acids that are used by cell to protein biosynthesis proteins. This is a non-essential amino acid and it is found in casein....
. Phenylalanine is converted to cinnamic acid

Cinnamic acid

Cinnamic acid has the formula C6H5CHCHCOOH and is a white crystalline acid, which is slightly soluble in water. It has a melting point of 133?C and a boiling point of 300?C....
 by the enzyme phenylalanine ammonia lyase.

Phenylketonuria

The genetic disorder phenylketonuria

Phenylketonuria

Phenylketonuria is an Dominance genetic disorder characterized by a deficiency in the enzyme phenylalanine hydroxylase . This enzyme is necessary to metabolize the amino acid phenylalanine to the amino acid tyrosine....
 (PKU) is the inability to metabolize phenylalanine. Individuals with this disorder are known as "phenylketonurics" and must abstain from consumption of too much phenylalanine. This dietary restriction also applies to pregnant women with hyperphenylalanine (high levels of phenylalanine in blood) because they do not metabolize the amino acid phenylalanine properly. Persons suffering from PKU must monitor their intake of protein to control the buildup of phenylalanine as their bodies convert protein into its component amino acids.

A non food source of phenylalanine is the artificial sweetener aspartame

Aspartame

Aspartame is the name for an artificial, non-saccharide sweetener, aspartyl-phenylalanine-1-methyl ester; that is, a methyl ester of the dipeptide of the amino acids aspartic acid and phenylalanine....
. This compound, sold under the trade names "Equal" and "NutraSweet", is metabolized by the body into several chemical byproducts including phenylalanine. The breakdown problems phenylketonurics have with protein and the attendant build up of phenylalanine in the body also occurs with the ingestion of aspartame, although to a lesser degree. Accordingly, all products in Australia, the U.S. and Canada that contain aspartame must be labeled: "Phenylketonurics: Contains phenylalanine." In the UK, foods containing aspartame must carry ingredients panels that refer to the presence of "aspartame or E951" and they must be labeled with a warning "Contains a source of phenylalanine." These warnings are specifically placed to aid individuals who suffer from PKU so that they can avoid such foods.

In Non-Humans

Geneticists have recently sequenced the genome of macaques. Their investigations have found "some instances where the normal form of the macaque protein looks like the diseased human protein" including markers for PKU.

D- and DL-phenylalanine

The unnatural stereoisomer D-phenylalanine (DPA) can be produced by conventional organic synthesis

Organic synthesis

Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic_chemistry molecules can often contain a higher level of complexity compared to purely Inorganic_chemistry compounds, so the synthesis of organic compounds has developed into one of the most im...
, either as a single enantiomer

Enantiomer

In chemistry, an enantiomer is one of two stereoisomers that are Superpose complete mirror images of each other, much as one's left and right Chirality are "the same" but opposite....
 or as a component of the racemic

Racemic

In chemistry, a racemic mixture, or racemate, is one that has equal Amount of substance of left- and right-handed enantiomer of a Chirality molecule....
 mixture. It does not participate in protein biosynthesis

Protein biosynthesis

Protein synthesis is the process in which cell build proteins. The term is sometimes used to refer only to protein translation but more often it refers to a multi-step process, beginning with amino acid synthesis and transcription which are then used for translation ....
 although it is found in proteins in small amounts - particularly aged proteins and food proteins that have been processed. The biological functions of D-amino acids remain unclear although some, such as D-phenylalanine, may have pharmacological activity.

DL-Phenylalanine (DLPA) is marketed as a nutritional supplement for its supposed analgesic

Analgesic

An analgesic is any member of the diverse group of Medication used to relieve pain . The word analgesic derives from Greek an- and algos ....
 and antidepressant

Antidepressant

An antidepressant is a psychiatric medication used for alleviating major depressive disorder or dysthymia. Drug groups known as MAOIs, tricyclics, and second-generation antidepressants such as SSRIs, and serotonin-norepinephrine reuptake inhibitors are particularly associated with the term....
 activities. The reputed analgesic activity of DL-phenylalanine may be explained by the possible blockage by D-phenylalanine of enkephalin

Enkephalin

An enkephalin is a pentapeptide involved in regulating pain and nociception in the body. The enkephalins are termed endogenous ligands, or specifically endorphins, as they are internally derived and bind to the body's opioid receptors....
 degradation

Degradation

Degradation may refer to;* Degradation , metal band from Chicago, IL USA* Biodegradation, the processes by which organic substances are broken down by living organisms...
 by the enzyme

Enzyme

Enzymes are biomolecules that catalysis chemical reactions. Almost all enzymes are proteins. In enzymatic reactions, the molecules at the beginning of the process are called Substrate , and the enzyme converts them into different molecules, the products....
 carboxypeptidase A

Carboxypeptidase A

Carboxypeptidase A usually refers to the pancreatic exopeptidase which hydrolyzes peptide bonds of C-terminal residues with aromatic or aliphatic side chains....
. The mechanism of DL-phenylalanine's supposed antidepressant activity may be accounted for by the precursor

Protein precursor

A protein precursor, also called a pro-protein or pro-peptide, is an inactive protein that can be turned into an active form by posttranslational modification....
 role of L-phenylalanine in the synthesis of the neurotransmitters, norepinephrine

Norepinephrine

Norepinephrine or noradrenaline is a catecholamine with dual roles as a hormone and a neurotransmitter.As a stress hormone, norepinephrine affects parts of the brain where attention and responding actions are controlled....
 and dopamine

Dopamine

Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the human brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors ? D1, D2, D3, D4 and D5, and their variants....
. Elevated brain levels of norepinephrine and dopamine are thought to have an antidepressant effect. Following ingestion, D-Phenylalanine is absorbed from the small intestine and transported to the liver via the portal circulation. A small amount of D-phenylalanine appears to be converted to L-phenylalanine. D-Phenylalanine is distributed to the various tissues of the body via the systemic circulation

Systemic circulation

Systemic circulation is the portion of the cardiovascular system which carries oxygenated blood away from the heart, to the body, and returns deoxygenated blood back to the heart....
. It appears to cross the blood-brain barrier

Blood-brain barrier

The blood-brain barrier is a metabolic or cellular structure in the central nervous system that restricts the passage of various chemical substances and microscopic objects between the bloodstream and the neural tissue itself, while still allowing the passage of substances essential to metabolism function ....
 less efficiently than L-phenylalanine, and so a small amount of an ingested dose of D-phenylalanine is not absorbed but excreted in the urine

Urine

Urine is a liquid waste product of the body secreted by the kidneys by a process of filtration from blood called urination and excreted through the urethra....
.

History

The genetic codon for phenylalanine was first discovered by J. Heinrich Matthaei and Marshall W. Nirenberg in 1961. They showed that by using

External links