tyrosine catabolic process
Definition
Target type: biologicalprocess
The chemical reactions and pathways resulting in the breakdown of tyrosine, an aromatic amino acid, 2-amino-3-(4-hydroxyphenyl)propanoic acid. [GOC:go_curators]
Tyrosine catabolism is the breakdown of the amino acid tyrosine, a process essential for energy production and the synthesis of various biomolecules. The breakdown of tyrosine begins with its conversion to p-hydroxyphenylpyruvate (HPP) through the enzyme tyrosine aminotransferase. HPP is then decarboxylated by the enzyme 4-hydroxyphenylpyruvate decarboxylase to form homogentisate. Homogentisate is then oxidized to maleylacetoacetate by the enzyme homogentisate 1,2-dioxygenase. Maleylacetoacetate is then isomerized to fumarylacetoacetate by the enzyme maleylacetoacetate isomerase. Finally, fumarylacetoacetate is cleaved by the enzyme fumarylacetoacetate hydrolase to form fumarate and acetoacetate. These two products are intermediates in the citric acid cycle and can be used for energy production. Tyrosine catabolism is also important for the synthesis of melanin, a pigment that gives skin, hair, and eyes their color. Tyrosine is converted to melanin through a series of enzymatic reactions involving the enzyme tyrosinase. Tyrosine catabolism is tightly regulated and is influenced by factors such as dietary intake of tyrosine, hormonal signals, and the activity of specific enzymes. Defects in tyrosine catabolism can lead to a number of genetic diseases, including alkaptonuria, tyrosinemia, and hereditary tyrosinemia type I. Alkaptonuria is characterized by the accumulation of homogentisate, which leads to the deposition of a black pigment in the urine, cartilage, and connective tissues. Tyrosinemia is characterized by the accumulation of tyrosine and its metabolites, which can lead to liver failure, kidney failure, and neurological problems. Hereditary tyrosinemia type I is the most severe form of tyrosinemia and can lead to death in early childhood. These diseases highlight the importance of tyrosine catabolism for normal human health.'
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Proteins (3)
| Protein | Definition | Taxonomy |
|---|---|---|
| 4-hydroxyphenylpyruvate dioxygenase | A 4-hydroxyphenylpyruvate dioxygenase that is encoded in the genome of Arabidopsis thaliana. [OMA:P93836, PRO:DNx] | Arabidopsis thaliana (thale cress) |
| 4-hydroxyphenylpyruvate dioxygenase | A 4-hydroxyphenylpyruvate dioxygenase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P32754] | Homo sapiens (human) |
| 4-hydroxyphenylpyruvate dioxygenase | A 4-hydroxyphenylpyruvate dioxygenase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P32754] | Homo sapiens (human) |
Compounds (8)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| pinocembrin | pinocembrin : A dihydroxyflavanone in which the two hydroxy groups are located at positions 5 and 7. A natural product found in Piper sarmentosum and Cryptocarya chartacea. | (2S)-flavan-4-one; dihydroxyflavanone | antineoplastic agent; antioxidant; metabolite; neuroprotective agent; vasodilator agent |
| sulcotrione | sulcotrione : An aromatic ketone that is cyclohexane-1,3-dione substituted by a 2-chloro-4-(methylsulfonyl)benzoyl group at position 2. sulcotrione: a bleaching herbicide | aromatic ketone; beta-triketone; cyclohexanones; sulfone | carotenoid biosynthesis inhibitor; environmental contaminant; herbicide; xenobiotic |
| nitisinone | (trifluoromethyl)benzenes; C-nitro compound; cyclohexanones; mesotrione | EC 1.13.11.27 (4-hydroxyphenylpyruvate dioxygenase) inhibitor | |
| mesotrione | mesotrione : An aromatic ketone that is cyclohexa-1,3-dione in which one of the hydrogens at position 2 is substituted by a 4-(methanesulfonyl)-2-nitrobenzoyl group. mesotrione: brandname is after the Callistemon (MYRTACEAE) plant it was found in; structure in first source | aromatic ketone; beta-triketone; C-nitro compound; sulfone | carotenoid biosynthesis inhibitor; EC 1.13.11.27 (4-hydroxyphenylpyruvate dioxygenase) inhibitor; environmental contaminant; herbicide; xenobiotic |
| (+)-usnic acid | usnic acid | ||
| leptospermone | leptospermone: a beta-triketone phloroglucinol derivative and constituent of essential oil extracted from Leptospermum scoparium (manuka oil); structure in first source | ||
| topramezone | topramezone : An aromatic ketone that is phenyl 1H-pyrazol-4-yl ketone in which the pyrazolyl group is substituted at positions 1 and 5 by methyl and hydroxy groups, respectively, and in which the phenyl group is substituted at positions 2, 3, and 4 by methyl, 4,5-dihydro-1,2-oxazol-3-yl, and methylsulfonyl groups, respectively. A potent inhibitor of 4-hydroxyphenylpyruvate dioxygenase (HPPD) that is rapily metabolised by corn to non-active substances, it is used as a herbicide for the treatment of broadleaf weeds. topramezone: corn herbicide, an inhibitor of 4-hydroxyphenylpyruvate dioxygenase; structure in first source | ||
| tembotrione | tembotrione : An aromatic ketone that is 2-benzoylcyclohexane-1,3-dione in which the phenyl group is substituted at positions 2, 3, and 4 by chlorine, (2,2,2-trifluoroethoxy)methyl, and methylsulfonyl groups, respectively. It is a post-emergence herbicide used (particularly in conjunction with the herbicide safener cyprosulfamide) for the control of a wide range of broad-leaved and grassy weeds in corn and other crops. | aromatic ketone; beta-triketone; cyclic ketone; ether; monochlorobenzenes; organofluorine compound; sulfone | agrochemical; carotenoid biosynthesis inhibitor; EC 1.13.11.27 (4-hydroxyphenylpyruvate dioxygenase) inhibitor; herbicide |