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Information about Tyrosine Hydroxylase

Tyrosine hydroxylase
Identifiers
SymbolTH
Entrez7054
HUGO11782
OMIM191290
RefSeqNM_000360
UniProtP07101
Other data
EC number1.14.16.2
LocusChr. 11 p15.5
Tyrosine hydroxylase or tyrosine 3-monooxygenase is the enzyme responsible for catalyzing the conversion of the amino acid L-tyrosine to dihydroxyphenylalanine (DOPA). DOPA is a precursor for dopamine which in turn is a precursor for norepinephrine (noradrenaline) and epinephrine (adrenaline).

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Tyrosine
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Dihydroxy
phenylalanine


The enzyme, an oxygenase, is found in the cytosol of all cells containing catecholamines. This initial reaction is the rate limiting step in the production of catecholamines.

The enzyme is highly specific, not accepting indole derivatives - which is unusual as many other enzymes involved in the production of catecholamines do.

Clinical significance

Tyrosine hydroxylase can be inhibited by the drug α-methyl tyrosine (Metirosine), however it is not an effective means of regulating noradrenaline synthesis. This drug is rarely used, but it is useful in treating pheochromocytoma and also resistant hypertension.

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Dopamine


Tyrosine hydroxylase is an autoantigen in Autoimmune Polyendocrine Syndrome (APS) type I.

References

External links

 •  • [ e]
Carrier proteins, metalloproteins: iron-binding proteins
hemeFerritin (Bacterioferritin) - Lactoferrin - Transferrin
nonhemeHemerythrin - Inositol oxygenase - Iron-sulfur protein - Lipoxygenase - Tyrosine hydroxylase


 •  • [ e]
Amino acid metabolism enzymes
phenylalanine->tyrosine->fumarate->TCAPhenylalanine hydroxylase - Tyrosine aminotransferase - 4-Hydroxyphenylpyruvate dioxygenase - Homogentisate 1,2-dioxygenase - Fumarylacetoacetate hydrolase
tyrosine->dopamine->epinephrineTyrosine hydroxylase - Aromatic L-amino acid decarboxylase - Dopamine beta hydroxylase - Phenylethanolamine N-methyltransferase
leucine->HMG-CoA (keto)Branched-chain alpha-keto acid dehydrogenase complex - Isovaleryl coenzyme A dehydrogenase - Methylcrotonyl-CoA carboxylase
isoleucine/valine->propionyl-CoABranched-chain alpha-keto acid dehydrogenase complex
methionine->cysteine->propionyl-CoAMethionine adenosyltransferase - Adenosylhomocysteinase - (or MTR) - Cystathionine beta synthase - Cystathionine gamma-lyase
propionyl-CoA->succinyl-CoA->TCAPropionyl-CoA carboxylase - Methylmalonyl-CoA mutase
serine->glycineSerine hydroxymethyltransferase
histidineto histamine: Histidine decarboxylase - to glutamate: Histidine ammonia-lyase - Urocanate hydratase - Formiminotransferase cyclodeaminase
tryptophan->serotonin->melatoninTryptophan hydroxylase - Aromatic L-amino acid decarboxylase - 5-hydroxyindole-O-methyltransferase
asparagine->aspartate->oxaloacetate->TCAAsparaginase/Asparagine synthetase - Aspartate transaminase
glutamateGlutaminase - Glutamate decarboxylase
lysine->ketoSaccharopine dehydrogenase
otherTyrosinase
The Entrez Global Query Cross-Database Search System is a powerful federated search engine, or web portal that allows users to search many discrete health sciences databases at the National Center for Biotechnology Information (NCBI) website.
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Hugo is a male given name, a latinized form of the name Hugh, a German/Teutonic name meaning "Bright in Mind and Spirit".

Hugo is one of the most popular names in Europe ranking as high as #2 in France, #6 in Spain, and #7 in Belgium in 2006.
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The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health. The NCBI is located in Bethesda, Maryland and was founded in 1988.
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Swiss-Prot is a manually curated biological database of protein sequences. Swiss-Prot was created in 1986 by Amos Bairoch during his PhD and developed by the Swiss Institute of Bioinformatics and the European Bioinformatics Institute.
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Enzyme Commission number (EC number) is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. As a system of enzyme nomenclature, every EC number is associated with a recommended name for the respective enzyme.
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locus (plural loci) is a fixed position on a chromosome, such as the position of a gene or a biomarker (genetic marker). A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map.
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Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions.[1] In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products.
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amino acid is a molecule that contains both amine and carboxyl functional groups. In biochemistry, this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent.
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Tyrosine (abbreviated as Tyr or Y)[1] or 4-hydroxyphenylalanine, is one of the 20 amino acids that are used by cells to synthesize proteins. It is a non-essential amino acid and it is found in large quantities in casein.
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Dihydroxyphenylalanine is a derivative of phenylalanine.

See also

  • Levodopa
  • Tyrosine hydroxylase

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Dopamine is a hormone and neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In chemical structure, it is a phenethylamine.
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Norepinephrine (INN)(abbr. norepi or NE) or noradrenaline (BAN) is a catecholamine and a phenethylamine with chemical formula C8H11NO3. The natural stereoisomer is L -(−)-(R)-norepinephrine.
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Epinephrine (INN) (IPA: [ˌɛpɪˈnɛfrən]) or adrenaline (European Pharmacopoeia and BAN) (IPA: [əˈdrɛnələn]
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An oxygenase is any enzyme that oxidizes a substrate by transferring the oxygen from molecular oxygen O2 (as in air) to it. The oxygenases form a class of oxidoreductases; their EC number is EC 1.13 or EC 1.14.
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The cytosol (cf. cytoplasm, which also includes the organelles) is the internal fluid of the cell, and a portion of cell metabolism occurs here. Proteins within the cytosol play an important role in signal transduction pathways and glycolysis.
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Catecholamines are chemical compounds derived from the amino acid tyrosine containing catechol and amine groups. Some of them are biogenic amines. Catecholamines are water soluble and are 50% bound to plasma proteins, so they circulate in the bloodstream.
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The rate-determining step (RDS) is a chemistry term for the slowest step in a chemical reaction. The rate-determining step is often compared to the neck of a funnel; the rate at which water flows through the funnel is determined by the width of the neck, not by the speed at which
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Indole is an aromatic heterocyclic organic compound. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring.
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Metirosine is an antihypertensive drug. It inhibits the enzyme tyrosine hydroxylase and, therefore, catecholamine synthesis.

Clinical use

Metirosine is used in the treatment of phaeochromocytoma. It is contra-indicated for the treatment of essential hypertension.
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Pheochromocytoma
Classification & external resources

Medulla visible at bottom right.
ICD-10 C 74.1
ICD-9 255.6
ICD-O: M 8700/0
OMIM 171300
DiseasesDB 9912

eMedicine med/1816   radio/552 ped/1788
MeSH D010673 A
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Hypertension
Classification & external resources

ICD-10 I 10. ,I 11. ,I 12. ,
I 13. ,I 15.
ICD-9 401.x

OMIM 145500
DiseasesDB 6330
MedlinePlus 000468
eMedicine med/1106   ped/1097 emerg/267


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Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
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Carrier proteins are proteins that transport a specific substance or group of substances across intracellular compartments or in extracellular fluids (e.g. in the blood) or else across the cell membrane.
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In biochemistry, a metalloprotein is a generic term for a protein that contains a metal cofactor. The metal may be an isolated ion or may be coordinated with a nonprotein organic compound, such as the porphyrin found in hemoproteins.
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Iron-binding proteins are carrier proteins and metalloproteins which play many important roles in metabolism.

See also

  • Iron

External links

  • MeSH Iron-binding+proteins


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Identifiers
Symbol FTH1
Alt. Symbols FTHL6

Entrez 2495
HUGO 3976
OMIM 134770

RefSeq NM_002032
UniProt P02794
Other data

Locus Chr.
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Bacterioferritin (BFR) is an oligomeric protein containing both a binuclear iron centre and haem b. The tertiary and quaternary structure of BFR is very similar to that of ferritin. The physiological functions of BFR, which may be other than just iron uptake, are not clear.
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Lactoferrin (LF), a globular multifunctional protein with antimicrobial activity (bacteriocide, fungicide), is part of the innate defense, mainly at mucoses. Lactoferrin is found in milk and many mucosal secretions such as tears and saliva.
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Transferrin is a blood plasma protein for iron ion delivery. Transferrin is a glycoprotein, which binds iron very tightly but reversibly. Although iron bound to transferrin is less than 0.
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Hemerythrin (also spelled haemerythrin; from Greek words αίμα = blood and ερυθρός = red) is an oligomeric protein responsible for oxygen (O2
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