Congenital disorders of amino acid metabolism

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Congenital disorders of amino acid metabolism
AminoAcidball.svg
The general structure of an α-amino acid, with the amino group on the left and the carboxyl group on the right
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Inborn errors of amino acid metabolism are metabolic disorders which impair the synthesis and degradation of amino acids.

Contents

Types

Amino acid transport disorders

Amino acid storage disorders

Related Research Articles

<span class="mw-page-title-main">Methylmalonic acidemia</span> Medical condition

Methylmalonic acidemia, also called methylmalonic aciduria, is an autosomal recessive metabolic disorder that disrupts normal amino acid metabolism. It is a classical type of organic acidemia. The result of this condition is the inability to properly digest specific fats and proteins, which in turn leads to a buildup of a toxic level of methylmalonic acid in the blood.

Propionic acidemia, also known as propionic aciduria or propionyl-CoA carboxylase deficiency, is a rare autosomal recessive metabolic disorder, classified as a branched-chain organic acidemia.

Inborn errors of metabolism form a large class of genetic diseases involving congenital disorders of enzyme activities. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances (substrates) into others (products). In most of the disorders, problems arise due to accumulation of substances which are toxic or interfere with normal function, or due to the effects of reduced ability to synthesize essential compounds. Inborn errors of metabolism are often referred to as congenital metabolic diseases or inherited metabolic disorders. Another term used to describe these disorders is "enzymopathies". This term was created following the study of biodynamic enzymology, a science based on the study of the enzymes and their products. Finally, inborn errors of metabolism were studied for the first time by British physician Archibald Garrod (1857–1936), in 1908. He is known for work that prefigured the "one gene-one enzyme" hypothesis, based on his studies on the nature and inheritance of alkaptonuria. His seminal text, Inborn Errors of Metabolism, was published in 1923.

<span class="mw-page-title-main">Isovaleric acidemia</span> Medical condition disrupting normal metabolism

Isovaleric acidemia is a rare autosomal recessive metabolic disorder which disrupts or prevents normal metabolism of the branched-chain amino acid leucine. It is a classical type of organic acidemia.

<span class="mw-page-title-main">Maple syrup urine disease</span> Autosomal recessive metabolic disorder

Maple syrup urine disease (MSUD) is an autosomal recessive metabolic disorder affecting branched-chain amino acids. It is one type of organic acidemia. The condition gets its name from the distinctive sweet odor of affected infants' urine and earwax, particularly prior to diagnosis and during times of acute illness. It was described by John Menkes in the 1950s.

<span class="mw-page-title-main">Hartnup disease</span> Metabolic disorder

Hartnup disease is an autosomal recessive metabolic disorder affecting the absorption of nonpolar amino acids. Niacin is a precursor to nicotinamide, a necessary component of NAD+.

Glutaric acidemia type 1 (GA1) is an inherited disorder in which the body is unable to completely break down the amino acids lysine, hydroxylysine and tryptophan. Excessive levels of their intermediate breakdown products can accumulate and cause damage to the brain, but particularly the basal ganglia, which are regions that help regulate movement. GA1 causes secondary carnitine deficiency, as glutaric acid, like other organic acids, is detoxified by carnitine. Mental retardation may occur.

<span class="mw-page-title-main">Methylmalonyl-CoA mutase deficiency</span> Medical condition

Methylmalonyl-CoA mutase is a mitochondrial homodimer apoenzyme that focuses on the catalysis of methylmalonyl CoA to succinyl CoA. The enzyme is bound to adenosylcobalamin, a hormonal derivative of vitamin B12 in order to function. Methylmalonyl-CoA mutase deficiency is caused by genetic defect in the MUT gene responsible for encoding the enzyme. Deficiency in this enzyme accounts for 60% of the cases of methylmalonic acidemia.

<span class="mw-page-title-main">William Nyhan</span> American physician (born 1926)

William Leo Nyhan is an American physician best known as the co-discoverer of Lesch–Nyhan syndrome.

<span class="mw-page-title-main">Aminoaciduria</span> Medical condition

Aminoaciduria occurs when the urine contains abnormally high amounts of amino acids. In the healthy kidney, the glomeruli filter all amino acids out of the blood, and the renal tubules then reabsorb over 95% of the filtered amino acids back into the blood.

<span class="mw-page-title-main">Methylmalonic acid</span> Chemical compound

Methylmalonic acid (MMA) is a dicarboxylic acid that is a C-methylated derivative of malonic acid.

<span class="mw-page-title-main">Hypervalinemia</span> Medical condition

Hypervalinemia is a rare autosomal recessive metabolic disorder in which urinary and serum levels of the branched-chain amino acid valine are elevated, without related elevation of the branched-chain amino acids leucine and isoleucine. It is caused by a deficiency of the enzyme valine transaminase.

Organic acidemia is a term used to classify a group of metabolic disorders which disrupt normal amino acid metabolism, particularly branched-chain amino acids, causing a buildup of acids which are usually not present.

<span class="mw-page-title-main">Sodium-dependent neutral amino acid transporter B(0)AT1</span> Protein-coding gene in the species Homo sapiens

Sodium-dependent neutral amino acid transporter B(0)AT1 is a protein that in humans is encoded by the SLC6A19 gene.

Amino acid transport disorders are medical conditions associated with a failure of amino acids to be absorbed from the kidney or intestine.

<span class="mw-page-title-main">Hypertryptophanemia</span> Medical condition

Hypertryptophanemia is a rare autosomal recessive metabolic disorder that results in a massive buildup of the amino acid tryptophan in the blood, with associated symptoms and tryptophanuria.

<span class="mw-page-title-main">D-Glyceric acidemia</span> Medical condition

D-Glyceric acidemia is an inherited disease, in the category of inborn errors of metabolism. It is caused by a mutation in the gene GLYCTK, which encodes for the enzyme glycerate kinase.

Combined malonic and methylmalonic aciduria (CMAMMA), also called combined malonic and methylmalonic acidemia is an inherited metabolic disease characterized by elevated levels of malonic acid and methylmalonic acid. However, the methylmalonic acid levels exceed those of malonic acid. Some researchers have hypothesized that CMAMMA might be one of the most common forms of methylmalonic acidemia, and possibly one of the most common inborn errors of metabolism. Due to being infrequently diagnosed, it most often goes undetected.

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