ornithine


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

ornithine

 [or´nĭ-thēn]
an amino acid obtained from arginine by splitting of urea; it is an intermediate in urea biosynthesis.
ornithine carbamoyltransferase (ornithine transcarbamylase) an enzyme that catalyzes a reaction occurring in the liver mitochondria as part of the urea cycle.

or·ni·thine (Orn),

(ōr'ni-thēn, -thin),
2,5-Diaminovaleric acid; the l-isomer is the amino acid formed when l-arginine is hydrolyzed by arginase; not a constituent of proteins, but an important intermediate in the urea cycle; elevated levels seen in certain defects of the urea cycle.

ornithine

/or·ni·thine/ (or´nĭ-thēn) an amino acid obtained from arginine by splitting of urea; it is an intermediate in urea biosynthesis.

ornithine

(ôr′nə-thēn′)
n.
An amino acid, C5H12N2O2, not found in proteins, formed by hydrolyzing arginine and important in the formation of urea.

ornithine

[ôr′nithēn]
an amino acid, not a constituent of proteins, that is produced as an important intermediate substance in the urea cycle. It is formed by the hydrolization of arginine by arginase and is subsequently converted into citrulline. It decomposes by losing carbon dioxide, producing putrescine and a strong foul odor characteristic of decaying animal tissue. Also called diaminovaleric acid.

or·ni·thine

(ōr'ni-thēn)
The amino acid formed when l-arginine is hydrolyzed by arginase; an important intermediate in the urea cycle; elevated levels seen in certain defects of the urea cycle.

ornithine

dietary supplement which in combination with other amino acids arginine and lysine is claimed to increase muscle growth/lean body mass to a greater extent than strength training alone, but this has not been supported by properly designed trials. See also ergogenic aids; appendix 4.4 .

or·ni·thine

(Orn) (ōr'ni-thēn)
Amino acid formed when l-arginine is hydrolyzed by arginase; important intermediate in the urea cycle.

ornithine (ôr´nəthēn´),

n an amino acid, not a constituent of proteins, that is produced as an important intermediate substance in the urea cycle.
ornithine carbamoyltransferase,
n an enzyme in the blood that increases in patients with liver and other diseases.

ornithine

an amino acid obtained from arginine by the action of the enzyme arginase which also splits off urea; it is an intermediate in urea biosynthesis.

ornithine carbamoyl transferase (OCT), ornithine transcarbamoylase
see ornithine carbamoyl transferase.
ornithine cycle
alternative name for urea cycle since ornithine is the carrier of the nitrogens.
ornithine decarboxylase test
a means of identifying different members of the Enterobacteriaceae as well as other gram-negative bacteria.
ornithine-δaminotransferase
deficiency see gyrate atrophy.
References in periodicals archive ?
Ornithine transcarbamylase deficiency in the newborn infant.
1990) demonstrated that the endogenous synthesis of Arg in the kidney depends on the synthesis of ornithine and citrulline in the intestine.
Concentrations of arginine, citrulline and ornithine in plasma were influenced by oxidative stress (Table 5).
Effects of [alpha]-difluoromethylornithine, a specific irreversible inhibitor of ornithine decarboxylase, on nucleic acids and proteins in developing rat brain: critical perinatal periods for regional selectivity.
He was suffering from a potentially fatal disease known as ornithine transcarbamylase deficiency (OTD), which prevents the liver from breaking down protein.
INGREDIENTS INCLUDE: L Ornithine, L Arginine, L Carnitine.
Ethical concerns regarding gene therapy trials peaked in 1999, when Jesse Gelsinger, an 18-year-old patient with ornithine transcarbamylase deficiency, died shortly after undergoing an investigational gene transfer procedure using an adenoviral vector.
Gelsinger participated in a clinical trial designed to test a potential gene therapy for ornithine transcarbamylase deficiency.
Unfortunately, it's expensive, but you can raise your HGH with the right amounts of a few amino acids such as arginine, ornithine, creatine, and some exercise.
Yamakawa and Taira (1980) detected ornithine decarboxylase activity in B.
On September 17, 1999, four days after receiving a gene therapy infusion at the University of Pennsylvania, a young man from Arizona who had a genetic disease known as Ornithine Transcarbamylase Deficiency (OTC) died.
Gelsinger, who died on September 17, suffered a fatal immune reaction while participating in a study of the safety of a treatment for ornithine transcarbamylase deficiency, a hereditary liver disorder that, in Gelsinger's case, was not life-threatening and was controlled with medication.