Glutamine: a nitrogen source in urea synthesis

Glutamine: precursor or nitrogen donor for citrulline synthesis?

Although glutamine is considered the main precursor for citrulline synthesis, the current literature does not differentiate between the contribution of glutamine carbon skeleton vs. nonspecific nitrogen (i.e., ammonia) and carbon derived from glutamine oxidation. To elucidate the role of glutamine and nonspecific nitrogen in the synthesis of citrulline, l-[2-(15)N]- and l-[5-(15)N]glutamine and...

Blood Urea Nitrogen

Loop diuretics are used in patients with heart failure (HF) to relieve symptoms of systemic and pulmonary venous congestion. Despite their nearly universal use for this indication, loop diuretics have not been shown to improve survival—indeed, a number of recent studies suggest an adverse relationship between the use of loop diuretics and survival (1–3). This is plausible because loop diuretics...

Milk Urea Nitrogen Testing

Urea as a source of nitrogen for the biosynthesis of amino acids.

Urea has long been recognized as the principal end product of nitrogenous metabolism in mammals. In recent years, the possibility that monogastric animals might be able to decompose this substance, when administered preformed, has stimulated considerable interest. The presence of radioactive carbon dioxide in the expired air after the injection of urea labeled with Cl4 indicates that decomposit...

Isolation of a strain of Agrobacterium tumefaciens (Rhizobium radiobacter) utilizing methylene urea (ureaformaldehyde) as nitrogen source.

Methylene ureas (MU) are slow-release nitrogen fertilizers degraded in soil by microbial enzymatic activity. Improved utilization of MU in agricultural production requires more knowledge about the organisms and enzymes responsible for its degradation. A Gram-negative, MU-degrading organism was isolated from a soil in Sacramento Valley, California. The bacterium was identified as Agrobacterium t...