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C6H13O3N3 An amino acid formed in the synthesis of arginine from ornithine.



(also called α-amino-δ-ureidovaleric acid), H2NCONH(CH2)3CH(NH2)COOH, a natural amino acid.

Citrulline exists in the optically active L- and D-forms and in the racemic DL-form. L-citrulline is found as a free compound in the juice of watermelons and a number of other plants, in the tubers of legumes, and in the tissues of mammals (liver, kidney, brain, muscles, and blood). Citrulline is not a component of natural proteins. Citrulline is separated from enzymatic hydrolysates of casein as a result of arginine splitting. In many organisms, citrulline participates in the ornithine cycle, in which it serves as an intermediate in the biosynthesis of arginine from ornithine. In plants, citrulline also participates in nitrogen fixation.


Meister, A. Biokhimiia aminokislot. Moscow, 1961. (Translated from English.)
Lehninger, A. Biokhimiia: Molekuliarnye osnovy struktury i funktsii kletki. Moscow, 1976. (Translated from English.)
References in periodicals archive ?
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).
Acute intestinal failure in critically ill patients: Is plasma citrulline the right marker?
In publication-pending studies, Fish showed that ethanol can be fermented from the glucose, fructose, and sucrose in waste-stream juices--what's left after lycopene and citrulline are extracted.
The production of NO and citrulline by horseradish peroxidase from N-hydroxyarginine (NOHA) and [H.
That's why Texas A&M researchers are interested in breeding watermelon with higher levels of citrulline.
Unfortunately, for messy eaters like myself, there is more citrulline in the rind of the watermelon, which means you've got to make it through all of the soft, pink fruity bit.
The anti-CCP assay utilizes synthetic peptides containing citrulline and detects the presence of autoantibodies to citrullinated peptides.
Does combining citrulline with arginine improve benefits?
Nitric oxide (NO) a byproduct of the oxidative reaction catalysed by nitric oxide synthase (NOS) that converts L-arginine to citrulline, act as a pleiotropic mediator in various physiological and pathophysiological conditions.
He then covers inorganic osmolytes, sugars in dehydration caused by freezing, drought, salinity and other sources of stress, complex sugars, proline, glycinebetaine, polyamines, trehalose, fructan, ecotine, citrulline and ROS and antioxidants.
30) A synthetic circular peptide containing citrulline called CCP was found to be better at discriminating RA patients from other arthritis patients than either the perinuclear autoantibody test or the RF assays.
Scientists interested in determining the relative amounts of an important amino acid called citrulline that's present in different watermelon varieties were recently surprised to find it concentrated in the melons' rind.