18 Background: In rheumatoid arthritis (RA), anti-citrullinated protein/peptide antibodies (ACPAs) 19 are responsible for disease onset and progression, however, our knowledge is limited on ligand 20 binding affinities of autoantibodies with different citrulline-peptide specificity. 21 Methods: Citrulline-peptide specific ACPA IgGs were affinity purified and tested by ELISA. 22 Binding affiniti...

Hypocitrullinemia and hypoargininemia but hyperprolinemia are associated with elevated plasma concentration of lactate in infants. Because the small intestine may be a major organ for initiating proline catabolism via proline oxidase in the body and is the major source of circulating citrulline and arginine in neonates, we hypothesized that lactate is an inhibitor of intestinal synthesis of cit...

A polymerase chain reaction-based library screening procedure was used to isolate RcAAP3, an amino acid permease cDNA from castor bean (Ricinus communis). RcAAP3 is 1.7 kb in length, with an open reading frame that encodes a protein with a calculated molecular mass of 51 kD. Hydropathy analysis indicates that the RcAAP3 protein is highly hydrophobic in nature with nine to 11 putative transmembr...

The objective of this study was to evaluate the influence of ingested l-arginine, l-citrulline, and antioxidants (vitamins C and E) on the progression of atherosclerosis in rabbits fed a high-cholesterol diet. The fatty diet caused a marked impairment of endothelium-dependent vasorelaxation in isolated thoracic aorta and blood flow in rabbit ear artery in vivo, the development of atheromatous l...

The need for 50 gm. of citrulline for the thermal data being compiled in this laboratory (1, 2) led to the search for a suitable method of preparation of this compound. Of the methods available, the most practical were Kurtz’s ingenious three reaction degradation of arginine (3), and Wada’s tryptic digestion of casein (4). Each of these authors, however, reported the preparation of less than 2 ...

Sir: It was shown previously that both L[guanidino-14C] arginine and L-[ureido-14C] citrulline are efficient mitomycin (I) precursors which specifically label the carbamoyl-group of these antibiotics1,3. Sodium-[14C] carbonates', [14C] urea1) and potassium-[14C] cyanate3' are inefficient precursors and this is presumably due to either inefficient uptake or loss of the label as carbon dioxide fr...

Our recent publication showed that pharmacological blockade of arginases confers kidney protection in diabetic nephropathy via a nitric oxide (NO) synthase (NOS)3-dependent mechanism. Arginase competes with endothelial NOS (eNOS) for the common substrate L-arginine. Lack of L-arginine results in reduced NO production and eNOS uncoupling, which lead to endothelial dysfunction. Therefore, we hypo...

THE ONLY METHOD available at present for the routine determination of citrulline in blood is the one first described by Archibald (1). This method is based on the original observation of Fearon (2) that in strongly acid solution citrulline condenses with diacetylmonoxime (DAM) to produce a peach-colored complex. Since urea also reacts with DAM under these conditions, Archibald removed it by inc...

Citrullinemia-is one of several human diseases caused by a defect in the KrebsHenseleit urea cycle. In this disorder a deficiency of liver argininosuccinate synthetase has been reported.' 1\Iorrow and his colleagues have recently described an infant with this condition2 and a fibroblast-like cell line has been derived from a skin biopsy of this child. In studying minimal media requirements for ...

CC was shown to be necessary for the reaction with a partially purified system (l), confirming previous data obtained with cruder preparations (2, 3).’ However, the mechanism of this reaction was not clear, since CG did not disappear during the biosynthesis of citrulline (1). Some insight into the mechanism of the reaction was obtained from kinetic data (l), indicating an “activation” of CG in ...