Search results
Results from the WOW.Com Content Network
[1] [2] Normally, the breakdown of the amino acid tyrosine involves the conversion of 4-hydroxyphenylpyruvate to homogentisate by 4-hydroxyphenylpyruvate dioxygenase. Complete deficiency of this enzyme would lead to tyrosinemia III. In rare cases, however, the enzyme is still able to produce the reactive intermediate 1,2-epoxyphenyl acetic acid ...
Tyrosinemia type III is a rare disorder caused by a deficiency of the enzyme 4-hydroxyphenylpyruvate dioxygenase (EC 1.13.11.27), encoded by the gene HPD. [2] This enzyme is abundant in the liver, and smaller amounts are found in the kidneys. It is one of a series of enzymes needed to break down tyrosine.
4-Hydroxyphenylpyruvate dioxygenase (HPPD), also known as α-ketoisocaproate dioxygenase (KIC dioxygenase), is an Fe(II)-containing non-heme oxygenase that catalyzes the second reaction in the catabolism of tyrosine - the conversion of 4-hydroxyphenylpyruvate into homogentisate.
4-Hydroxyphenylpyruvate dioxygenase (HPPD) is an enzyme found in both plants and animals, which catalyzes the catabolism of the amino acid tyrosine. [4] Preventing the breakdown of tyrosine has three negative consequences: the excess of tyrosine stunts growth; the plant suffers oxidative damage due to lack of tocopherols (vitamin E); and ...
4-Hydroxyphenylpyruvic acid (4-HPPA) is an intermediate in the metabolism of the amino acid phenylalanine. The aromatic side chain of phenylalanine is hydroxylated by the enzyme phenylalanine hydroxylase to form tyrosine. The conversion from tyrosine to 4-HPPA is in turn catalyzed by tyrosine aminotransferase. [2]
In addition to the common amino acid L-tyrosine, which is the para isomer (para-tyr, p-tyr or 4-hydroxyphenylalanine), there are two additional regioisomers, namely meta-tyrosine (also known as 3-hydroxyphenylalanine, L-m-tyrosine, and m-tyr) and ortho-tyrosine (o-tyr or 2-hydroxyphenylalanine), that occur in nature.
Homogentisic acid (2,5-dihydroxyphenylacetic acid) is a phenolic acid usually found in Arbutus unedo (strawberry-tree) honey. [1] It is also present in the bacterial plant pathogen Xanthomonas campestris pv. phaseoli [2] as well as in the yeast Yarrowia lipolytica [3] where it is associated with the production of brown pigments.
The molecular formula C 9 H 8 O 4 (molar mass: 180.15 g/mol, exact mass: 180.0423 u) may refer to: Acetozone; Aspirin; 4-Hydroxyphenylpyruvic acid, a natural phenol; Dihydroxycinnamic acids: Caffeic acid (3,4-Dihydroxycinnamic acid) Umbellic acid (2,4-dihydroxycinnamic acid) 2,3-Dihydroxycinnamic acid; 2,5-Dihydroxycinnamic acid; 3,5 ...