Assay for glutamine synthetase activity.

Regulation of glutamine synthetase from Bacillus subtilis by divalent cations, feedback inhibitors, and L-glutamine.

Glutamine synthetase purified to apparent homogeneity from Bacillus subtilis is subject to feedback inhibition by multiple end products of glutamine metabolism, as well as by the reaction product L-glutamine. AMP, glutamine, and histidine are potent inhibitors when any of the substrates glutamate, MnATP, or ammonia are present in limiting concentration during assay, but the strong inhibition by...

Biochemical and molecular analysis of glutamine synthetase gene in brassica napus L.

A radiochemical assay for glutamine synthetase, and activity of the enzyme in rat tissues.

1. A radiochemical assay for glutamine synthetase has been developed in which an ATP-regenerating system is incorporated to prevent accumulation of inhibitory amounts of ADP. It is particularly suitable for assay of the enzyme in crude tissue extracts containing high adenosine triphosphatase activity. 2. A survey of the distribution of the enzyme in tissues from normal male rats showed that act...

Direct molecular and spectroscopic evidence for increased ammonia removal capacity of skeletal muscle in acute liver failure.

BACKGROUND/AIMS It has been proposed that, in acute liver failure, skeletal muscle adapts to become the principle organ responsible for removal of blood-borne ammonia by increasing glutamine synthesis, a reaction that is catalyzed by the cytosolic ATP-dependent enzyme glutamine synthetase. To address this issue, glutamine synthetase expression and activities were measured in skeletal muscle of ...

Purification and properties of glutamine synthetase from spinach leaves.

The chloroplastic glutamine synthetase of spinach leaves has been purified to homogeneity using affinity chromatography. This involves a tandem ;reactive blue A-agarose' and ;reactive red-A-agarose' as the final step in the procedure. This procedure results in a yield of 18 milligrams of pure glutamine synthetase per kilogram of starting material. The purity of our enzyme has been demonstrated ...