hyperlysinemias/reductase

Familial hyperlysinemias are autosomal recessive disorders in the oxidative degradation of lysine. Hyperlysinemia type I is associated with a combined deficiency in lysine-ketoglutarate reductase and saccharopine dehydrogenase activities, the first two sequential steps in the lysine degradative

A 7-year-old boy with speech delay, hyperactive behavior, and minor neurologic abnormalities had been found in the past to have "intermittent cystinuria." A more detailed investigation revealed hyperlysinemia and hyperlysinuria, with lesser increases in urinary excretion of arginine and cystine. The

Fibroblasts grown in tissue culture from the skin of normal subjects have lysine-ketoglutarate reductase activity (lysine: alpha-ketoglutarate: triphosphopyridine nucleotide (TPNH) oxidoreductase (epsilon-N-[L-glutaryl-2]-L-lysine forming)). The activity of the enzyme is considerably reduced in the

Dienoyl-CoA reductase (DECR) deficiency with hyperlysinemia is a rare disorder affecting the metabolism of polyunsaturated fatty acids and lysine. The molecular basis of this condition is currently unknown. We describe a new case with failure to thrive, developmental delay, lactic acidosis and

Ten patients with familial hyperlysinemia with lysine-ketoglutarate reductase deficiency, identified through newborn screening programs or family surveys, were selected for review. Ages ranged from 2 to 24 years when last examined. A low-protein diet had been administered to two patients, which

A female infant with episodic hyperammonemia due to a disorder of the urea cycle and who had hyperlysinemia and an unusual elevation of short chain fatty acids, mainly propionate, is described. Both occurred apparently only during attacks of hyperammonemia. Propionic acidemia was ruled out by enzyme

Several inherited disorders of fatty acid beta-oxidation have been described that relate mainly to saturated precursors. This study is the first report of an enzyme defect related only to unsaturated fatty acid oxidation and provides the first in vivo evidence that fat oxidation in humans proceeds

Enzyme assays of skin fibroblasts from five children with familial hyperlysinemia from unrelated families are added to the previous report of three children from two unrelated families. In all instances there was a deficiency in lysine-ketoglutarate reductase, saccharopine dehydrogenase, and

A three-year-old asymptomatic boy with hyperlysinemia is presented. The patient's plasma lysine levels have been constantly high (685-1370 mumol/l) and excessive urinary excretion of ornithine, arginine and cystine have been noted. There was no detectable activity of lysine-ketoglutarate reductase

The first two steps in the mammalian lysine-degradation pathway are catalyzed by lysine-ketoglutarate reductase and saccharopine dehydrogenase, respectively, resulting in the conversion of lysine to alpha-aminoadipic semialdehyde. Defects in one or both of these activities result in familial

Lysine-ketoglutarate reductase (EC. 1.5.1.8) deficiency in skin fibroblasts has been previously reported in patients with familial hyperlysinemia, providing an adequate explanation for the biochemical derangements noted clinically. In the present study, analysis of liver obtained at autopsy from a

Yeast supersuppressor genes capable of masking the effects of several lysine mutant genes (ly(1-1), ly(9-1), ly(2-1)) were studied with respect to their effects on the respective enzymes (saccharopine dehydrogenase, saccharopine reductase, and alpha-amino-adipic acid reductase). In all strains

Mitochondrial NAD kinase deficiency (NADK2D, OMIM #615787) is a rare autosomal recessive disorder of NADPH biosynthesis that can cause hyperlysinemia and dienoyl-CoA reductase deficiency (DECRD, OMIM #616034). NADK2 deficiency has been reported in only three unrelated patients. Two had severe,

Alpha-aminoadipate delta-semialdehyde synthase (AASS) is the bifunctional enzyme containing the lysine alpha-ketoglutarate reductase (LKR) and saccharopine dehydrogenase activities responsible for the first 2 steps in the irreversible catabolism of lysine. A rare disease in humans, familial

Pipecolic acid (PA) levels are increased in severe metabolic disorders of the central nervous system such as Zellweger syndrome, infantile Refsum disease, neonatal adrenoleukodystrophy and hyperlysinemia. The affected individuals present progressive neurological dysfunction, hypotonia and growth