Ornithine


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Related to Ornithine: Ornithine cycle, Ornithine decarboxylase, Ornithine transcarbamylase deficiency

ornithine

[′ȯr·nə‚thēn]
(biochemistry)
C5H12O2N2 An amino acid occurring in the urine of some birds, but not found in native proteins.

Ornithine

 

H2N(CH2)3CH(NH2)COOH (also α, δ-di-aminovaleric acid), an amino acid that is readily soluble in water and alcohol.

Ornithine has one asymmetric carbon atom and exists in two optically active forms (D- and L-) and one racemic form, L-ornithine, found in the tissues of animals and humans, plays an important role in the biosynthesis of urea by the ornithine cycle. It is formed from arginine and α-amino-y-formylbutyric acid and may be converted to proline. Free L-ornithine is found in plants; bound L-ornithine is a component of several peptide antibiotics (bacitracin and gramicidin). L-ornithine has not been isolated from natural proteins.

References in periodicals archive ?
Mutations and polymorphisms in the human ornithine transcarbamylase gene.
2]S - - - production Acetamidase + NA - NA Nitrate reduction + + - NA [alpha]-Methyl- - - + + D-glucoside Indole + + + + DNA - + - NA Arginine - - - dihydrolase Ornithine - + + + decarboxylase Lysine + + + 4- decarboxylase Growth at NaCl 0% 1% + + + + 3% + + + + 6% + + + + 0/129 10 [micro]g S S S s 150 [micro]g S s s s +, positive; negative; F, fermentative; NA, not available; S, sensitive; v, variable between strains.
Elam RP, Hardin DH, Sutton RA, Hagen L (1989) Effects of arginine and ornithine on strength, lean body mass and urinary hydroxyproline in adult males.
Four of the seven identified metabolites--histidine, arginine, ornithine and glutamine--are related to genes involved in arginine-glutamine metabolism and nitrogen compound biosynthesis.
Tamir and Ratner (1963) attributed birds' incapacity to synthesize ornithine, citrulline and Arg to the absence of another enzyme key to the urea cycle, ornithine carbamoyltransferase (Figure 2).
The concentrations of the amino acids cysteine, methionine, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, isoleucine, leucine, tyrosine, phenylalanine, histidine, ornithine, lysine, arginine, hydroxyproline, tryptophan and taurine were nearly identical in kapenta compared to FPC (Table 1).
Measurement of OAT activity: The activity of ornithine aminotransferase (OAT) was determined as described by Wu et al.
The peak separation is >95% on common amino acids profile (up to 45 amino acids in a single run with Lithium systems), including Taurine, Ornithine, oxidized amino acids such as Cysteic acid and Methionine Sulfone, and hydroxylated amino acids such as Hydroxyproline and Hydroxylysine.
Jesse, who was eighteen years old, was participating in a phase I safety study of a gene transfer therapy for ornithine transcarbamylase deficiency (OTCD), a rare metabolic condition.
In particular, for ameliorating the symptoms or onset of amyotrophic lateral sclerosis (ALS) by modulating the gene and protein products involved the polyamine pathway, such as by inhibiting the enzyme, ornithine decarboxylase (ODC), involved in the synthesis of the polyamine, putrescine.
beverage called Office Diet, formulated with carnitine, ornithine and