ammonia is a toxic material for mammalians. it is detoxificated and converted to urea in the urea cycle in liver. each defect in the urea cycle cause increase in blood ammonia level. ornithine transcarbamylase enzyme (otc) is the second enzyme in the urea cycle that exists in mitochondria. otc deficiency is the most common hereditary disorder in the urea cycle. in this study, 45 hyper ammonia p...

Escherichia coli possesses two acyl ornithine aminotransferases, one catabolic (AstC) and the other anabolic (ArgD), that participate in L-arginine metabolism. Although only 58% identical, the enzymes have been shown to be functionally interchangeable. Here we have purified AstC and have obtained X-ray crystal structures of apo and holo-AstC and of the enzyme complexed with its physiological su...

A linked-function analysis of the allosteric responsiveness of carbamoyl phosphate synthetase (CPS) from E. coli was performed by following the ATP synthesis reaction at low carbamoyl phosphate concentration. All three allosteric ligands, ornithine, UMP, and IMP, act by modifying the affinity of CPS for the substrate MgADP. Individually ornithine strongly promotes, and UMP strongly antagonizes,...

OBJECTIVE To determine the efficacy of L-ornithine-L-aspartate in treatment of hepatic encephalopathy. STUDY DESIGN Randomized, placebo-controlled trial. PLACE AND DURATION OF STUDY Department of Gastroenterology and Hepatology, Sheikh Zayed Hospital, Lahore, from February to August 2005. METHODOLOGY Cirrhotic patients with hyperammonemia and overt hepatic encephalopathy were enrolled. Ei...

Ornithine decarboxylase, the first enzyme of the polyamine biosynthetic pathway, is induced by androgens in the mouse kidney. We have isolated from a kidney cDNA clone bank two plasmids, pODC1440 and pODC934 , that contain different cDNA inserts corresponding to ornithine decarboxylase mRNA. Identification was based upon the ability of plasmid-specific mRNAs to encode a 53,000-dalton polypeptid...

The arginine deiminase (ADI) pathway converts L-arginine into L-ornithine and yields 1 mol of ATP per mol of L-arginine consumed. The L-arginine/L-ornithine exchanger in the pathway takes up L-arginine and excretes L-ornithine from the cytoplasm. Analysis of the genomes of 1281 bacterial species revealed the presence of 124 arc gene clusters encoding the pathway. About half of the clusters cont...

Abstract Background The biomarkers of atherosclerosis remain insufficiently understood. Purpose We sought to investigate whether an altered balance arginine metabolites in patients following myocardial infarction (MI) is associated with remodeling the adjacent culprit segments infarct-related artery (IRA) and clinical outcomes. Methods Arginine its including ornithine, citrulline, proline asymm...

An enzyme was extensively purified from jack bean leaves (Canavalia ensiformis L.) which produced o-ureidohomoserine from l-canaline and carbamyl phosphate. The most highly purified preparations catalyzed both this reaction and citrulline synthesis from ornithine and carbamyl phosphate, and the ratio of the two activities remained nearly constant during purification. When hydrated jack bean see...

Aim. To analyse effectiveness of introduced genes ornithine-δ-aminotransferase (oat) Medicago truncatula and fragments two copies first exon intron the gene prolinedehydrogenase (pdh) Arabidopsis thaliana, that form double stranded RNA suppressor wheat, in increase her productivity for actions ofosmotic stress. Methods. Determination content free L-proline (Pro); activity enzyme (OAT), proline ...