GLUL Human

Glutamine synthetase (GS) is a crucial enzyme in nitrogen metabolism, catalyzing the ATP-dependent conversion of glutamate and ammonia to glutamine. This enzyme plays a vital role in various physiological processes, including nitrogen detoxification, neurotransmitter regulation, and cellular metabolism. The human recombinant form of glutamine synthetase is widely used in research and industrial applications due to its high purity and consistent activity.

Glutamine synthetase is a homodecameric enzyme composed of ten identical subunits arranged in a two-tiered ring structure. Each subunit contains an active site where the catalytic reaction occurs. The enzyme’s activity is regulated by various factors, including feedback inhibition by its end product, glutamine, and covalent modification through adenylylation.

1. Nitrogen Metabolism: GS is essential for the detoxification of ammonia, a byproduct of amino acid metabolism. By converting ammonia to glutamine, GS helps maintain nitrogen balance and prevents the toxic accumulation of ammonia in tissues.
2. Neurotransmitter Regulation: In the brain, GS is involved in the synthesis of glutamine, which serves as a precursor for the neurotransmitters glutamate and gamma-aminobutyric acid (GABA). This regulation is critical for maintaining neurotransmitter homeostasis and proper neuronal function.
3. Cellular Metabolism: Glutamine produced by GS is a key nutrient for rapidly proliferating cells, such as cancer cells and immune cells. It supports various metabolic pathways, including nucleotide biosynthesis, energy production, and redox balance.

GS is ubiquitously expressed in various tissues, with particularly high levels in the liver, brain, and kidneys. In the liver, GS is primarily located in perivenous hepatocytes, where it plays a role in ammonia detoxification. In the brain, GS is predominantly expressed in astrocytes, supporting neurotransmitter cycling and protecting neurons from excitotoxicity. In the kidneys, GS contributes to the regulation of acid-base balance by facilitating ammonia excretion.

Human recombinant glutamine synthetase is produced using advanced biotechnological methods. The gene encoding human GS is cloned into an expression vector and introduced into a suitable host cell system, such as Escherichia coli or Chinese hamster ovary (CHO) cells. The recombinant protein is then purified using chromatographic techniques to achieve high purity and activity levels .

1. Research: Recombinant GS is used in various research applications, including studies on nitrogen metabolism, neurotransmitter regulation, and cancer metabolism. It serves as a valuable tool for investigating the enzyme’s structure-function relationships and regulatory mechanisms.
2. Industrial Production: GS-based expression systems are employed in the production of therapeutic proteins and antibodies. The enzyme’s ability to facilitate high-yield protein expression makes it an attractive choice for biopharmaceutical manufacturing .
3. Clinical Diagnostics: GS activity assays are used in clinical diagnostics to assess liver and brain function. Abnormal GS activity levels can indicate liver disease, neurodegenerative disorders, or metabolic imbalances .