A urea cycle disorder manifesting in infancy as lethargy, emesis, seizures, alterations of muscle tone, abnormal eye movements, and an elevation of serum ammonia. The disorder is caused by a reduction in the activity of hepatic mitochondrial CARBAMOYL-PHOSPHATE SYNTHASE (AMMONIA). (Menkes, Textbook of Child Neurology, 5th ed, pp50-1)

The monoanhydride of carbamic acid with PHOSPHORIC ACID. It is an important intermediate metabolite and is synthesized enzymatically by CARBAMYL-PHOSPHATE SYNTHASE (AMMONIA) and CARBAMOYL-PHOSPHATE SYNTHASE (GLUTAMINE-HYDROLYZING).

An enzyme that catalyzes the formation of carbamoyl phosphate from ATP, carbon dioxide, and ammonia. This enzyme is specific for arginine biosynthesis or the urea cycle. Absence or lack of this enzyme may cause CARBAMOYL-PHOSPHATE SYNTHASE I DEFICIENCY DISEASE. EC 6.3.4.16.

Diseases caused by the loss of one or more enzymes involved in the hydrolysis of mannoside linkages (MANNOSIDASES). The defects in enzyme activity are primarily associated with genetic mutation of the genes that codes for a particular mannosidase isoenzyme.

An enzyme that catalyzes the formation of carbamoyl phosphate from ATP, carbon dioxide, and glutamine. This enzyme is important in the de novo biosynthesis of pyrimidines. EC 6.3.5.5.

Syndromes in which there is a deficiency or defect in the mechanisms of immunity, either cellular or humoral.

An enzyme that catalyzes the formation of myo-inositol-1-phosphate from glucose-6-phosphate in the presence of NAD. EC 5.5.1.4.

A urea cycle enzyme that catalyzes the formation of orthophosphate and L-citrulline (CITRULLINE) from CARBAMOYL PHOSPHATE and L-ornithine (ORNITHINE). Deficiency of this enzyme may be transmitted as an X-linked trait. EC 2.1.3.3.

An inherited metabolic disorder characterized by the intralysosomal accumulation of sulfur-containing lipids (sulfatides) and MUCOPOLYSACCHARIDES. Excess levels of both substrates are present in urine. This is a disorder of multiple sulfatase (arylsulfatases A, B, and C) deficiency which is caused by the mutation of sulfatase-modifying factor-1. Neurological deterioration is rapid.

An enzyme of the shikimate pathway of AROMATIC AMINO ACID biosynthesis, it generates 5-enolpyruvylshikimate 3-phosphate and ORTHOPHOSPHATE from PHOSPHOENOLPYRUVATE and shikimate-3-phosphate. The shikimate pathway is present in BACTERIA and PLANTS but not in MAMMALS.

An enzyme that catalyzes the formation of 7-phospho-2-keto-3-deoxy-D-arabinoheptonate from phosphoenolpyruvate and D-erythrose-4-phosphate. It is one of the first enzymes in the biosynthesis of TYROSINE and PHENYLALANINE. This enzyme was formerly listed as EC 4.1.2.15.

An enzyme that catalyzes the conversion of carbamoyl phosphate and L-aspartate to yield orthophosphate and N-carbamoyl-L-aspartate. (From Enzyme Nomenclature, 1992) EC 2.1.3.2.

A flavoprotein and iron sulfur-containing oxidoreductase complex that catalyzes the conversion of UBIQUINONE to ubiquinol. In MITOCHONDRIA the complex also couples its reaction to the transport of PROTONS across the internal mitochondrial membrane. The NADH DEHYDROGENASE component of the complex can be isolated and is listed as EC 1.6.99.3.

An enzyme that catalyzes the transfer of glucose from ADPglucose to glucose-containing polysaccharides in 1,4-alpha-linkages. EC 2.4.1.21.

An autosomal recessive metabolic disorder caused by absent or decreased PYRUVATE CARBOXYLASE activity, the enzyme that regulates gluconeogenesis, lipogenesis, and neurotransmitter synthesis. Clinical manifestations include lactic acidosis, seizures, respiratory distress, marked psychomotor delay, periodic HYPOGLYCEMIA, and hypotonia. The clinical course may be similar to LEIGH DISEASE. (From Am J Hum Genet 1998 Jun;62(6):1312-9)

Derivatives of carbamic acid, H2NC(=O)OH. Included under this heading are N-substituted and O-substituted carbamic acids. In general carbamate esters are referred to as urethanes, and polymers that include repeating units of carbamate are referred to as POLYURETHANES. Note however that polyurethanes are derived from the polymerization of ISOCYANATES and the singular term URETHANE refers to the ethyl ester of carbamic acid.

Inorganic salts of phosphoric acid.

A group of metabolic disorders primarily of infancy characterized by the subacute onset of psychomotor retardation, hypotonia, ataxia, weakness, vision loss, eye movement abnormalities, seizures, dysphagia, and lactic acidosis. Pathological features include spongy degeneration of the neuropile of the basal ganglia, thalamus, brain stem, and spinal cord. Patterns of inheritance include X-linked recessive, autosomal recessive, and mitochondrial. Leigh disease has been associated with mutations in genes for the PYRUVATE DEHYDROGENASE COMPLEX; CYTOCHROME-C OXIDASE; ATP synthase subunit 6; and subunits of mitochondrial complex I. (From Menkes, Textbook of Child Neurology, 5th ed, p850).

An amino acid produced in the urea cycle by the splitting off of urea from arginine.

Enzymes that catalyze a reverse aldol condensation. A molecule containing a hydroxyl group and a carbonyl group is cleaved at a C-C bond to produce two smaller molecules (ALDEHYDES or KETONES). EC 4.1.2.

Diseases caused by abnormal function of the MITOCHONDRIA. They may be caused by mutations, acquired or inherited, in mitochondrial DNA or in nuclear genes that code for mitochondrial components. They may also be the result of acquired mitochondria dysfunction due to adverse effects of drugs, infections, or other environmental causes.