GLUL Human, Active
Description
Product Specs
Product Science Overview
Glutamine synthetase (GS), also known as glutamate-ammonia ligase, is an enzyme that plays a crucial role in nitrogen metabolism. It catalyzes the ATP-dependent condensation of glutamate and ammonia to form glutamine. This reaction is vital for various cellular processes, including energy production, cell proliferation, inhibition of apoptosis, and cell signaling .
Glutamine synthetase is a multi-subunit enzyme, typically composed of 8, 10, or 12 identical subunits arranged in a symmetrical manner. Each subunit contains an active site where the catalytic reaction occurs. The enzyme’s structure allows it to bind to substrates such as ATP, glutamate, and ammonia, facilitating the formation of glutamine .
The enzyme’s active site is located between two monomers, with specific binding sites for cations, ADP, and other molecules. The binding of these molecules is essential for the enzyme’s catalytic activity. The enzyme’s structure also includes binding sites for divalent cations like Mn²⁺ or Mg²⁺, which are crucial for stabilizing the enzyme and facilitating the phosphoryl transfer of ATP to glutamate .
Glutamine synthetase is expressed during early fetal stages and plays a significant role in maintaining body pH by removing ammonia from circulation. It is also involved in various metabolic pathways, including amino acid degradation, nitrate reduction, and photorespiration. The enzyme’s activity is regulated by the concentration of ammonium ions and water, which compete for binding at the active site .
Mutations in the GLUL gene, which encodes glutamine synthetase, are associated with congenital glutamine deficiency, a condition that can lead to severe neurological and developmental issues .
Recombinant human glutamine synthetase is produced using Escherichia coli (E. coli) expression systems. The recombinant enzyme is a single, non-glycosylated polypeptide chain containing 373 amino acids and has a molecular mass of approximately 42 kDa . The enzyme is typically formulated in a buffer solution containing Tris-HCl, glycerol, DTT, and PMSF to maintain its stability and activity .
The specific activity of recombinant human glutamine synthetase is defined as the amount of enzyme that converts L-glutamate to L-glutamine per minute at pH 7.5 and 37°C. This activity is crucial for various laboratory research applications, including studies on cell proliferation, apoptosis, and metabolic regulation .
Recombinant human glutamine synthetase is widely used in laboratory research to study its role in cellular metabolism and its potential therapeutic applications. The enzyme’s ability to catalyze the formation of glutamine makes it a valuable tool for investigating metabolic pathways and understanding the mechanisms underlying various diseases .
In addition, glutamine synthetase is used as a selectable marker in genetic engineering and cell culture studies. NS0 cells, which have low endogenous glutamine synthetase activity, can be transfected with the enzyme to identify successful transfectants in the absence of glutamine in the media .
