L-Glutamine Synthetase from Escherichia coli

General description

L-Glutamine Synthetase from bacteria shows dodecameric structure comprising of 12 active sites. Each active site termed bifunnel, has an ATP and glutamate binding sites. The dodecamer is stabilized by two hexameric rings.

Application

L-Glutamine Synthetase from Escherichia coli has been used in the synthesis of methylglutamine from methylammonium in E coli and in the glutamine synthetase protection activity of human thioredoxin peroxidase enzyme, AOE372.

L-Glutamine synthetase may be used for the purification of proteases from Escherichia coli.

Biochem/physiol Actions

L-glutamine synthetase catalyzes the condensation of L-glutamate and ammonia to L-glutamine. It is a degradative enzyme for glutamic acid.

Nitrogen starvation dictates the expression of the glutamine synthetase (GS) gene in E. coli. GS plays a key role in ammonia assimilation in bacteria. Adenylylation of GS is catalyzed by adenylyltransferase. Adenylylation of GS modulates its catalytic functionality resulting in glutamine limitation in E coli.

Degradative enzyme for glutamic acid

Unit Definition

One unit will convert 1.0 μmole of L-glutamate to L-glutamine in 15 min at pH 7.1 at 37 °C.

Physical form

Contains potassium phosphate, sodium citrate and magnesium acetate buffer salts