Homogentisate 1,2-dioxygenase (homogentisic acid oxidase, homogentisate oxidase, homogentisicase) is an enzyme which catalyzes the conversion of homogentisate to 4-maleylacetoacetate. Homogentisate 1,2-dioxygenase or HGD is involved in the catabolism of aromatic rings, more specifically in the breakdown of the amino acids tyrosine and ...

2019年2月8日 · We found a small but statistically significant difference in urinary homogentisic acid (HGA) excretion, corrected for dietary protein intake, between variants leading to 1% or >30% residual HGD...

The HGD gene provides instructions for making an enzyme called homogentisate oxidase, which is active chiefly in the liver and kidneys. This enzyme participates in a step-wise process that breaks down two protein building blocks (amino acids), phenylalanine and tyrosine, when they are no longer needed or are present in excess.

2024年12月25日 · HGD (Homogentisate 1,2-Dioxygenase) is a Protein Coding gene. Diseases associated with HGD include Alkaptonuria and Tyrosinemia. Among its related pathways are Tyrosine catabolism and Metabolism. Gene Ontology (GO) annotations related to this gene include homogentisate 1,2-dioxygenase activity.

In humans, homogentisate 1,2-dioxygenase catalyzes the cleavage of the homogentisate ring, produced by 4-hydroxyphenylpyruvate dioxygenase in the degradation pathway of tyrosine, to yield maleylacetoacetate.

Because the enzyme homogentisic acid oxidase (homogentisate 1,2-dioxygenase) is lacking, homogentisic acid deposits in tissues (especially cartilage, elastic, and collagen, e.g., sclera) and forms a melanin-like substance. II. Homogentistic acid in the urine, which oxidizes on standing to produce a dark, melanin-like product.

2025年1月4日 · Title: Homogentisate 1,2-dioxygenase (HGD) gene variants, their analysis and genotype-phenotype correlations in the largest cohort of patients with AKU. Twelve novel HGD gene variants have been identified in 99 alkaptonuria patients affecting the bones.

Four different mutations of the HGD gene were found in alkaptonuria and ochronotic arthropathy diagnoses. This gene encodes the enzyme homogentisate 1,2 dioxygenase. This enzyme is involved in the catabolism of the amino acids tyrosine and phenylalanine.

Here we report the first crystal structure of a eukaryotic dioxygenase that catalyzes an aromatic ring cleavage reaction. The HGO structure and mechanism proposed here may help in the design of...

2004年1月1日 · Homogentisate 1,2-dioxygenase (HGD) is a mononuclear Fe(II)-dependent oxygenase that catalyzes the third step in the pathway for the catabolism of tyrosine, the conversion of homogentisate (HG) to maleylacetoacetate (MAA). We have heterologously expressed and purified native human HGD in the apo form.