GDA Human
Description
Product Specs
Product Science Overview
GDA is a cytoplasmic enzyme found in various tissues, including the brain, liver, and kidneys. The enzyme’s primary function is to convert guanine into xanthine, which is then further metabolized into uric acid by xanthine oxidase . This process is vital for maintaining the balance of purine nucleotides within the cell and preventing the accumulation of toxic guanine levels.
The human GDA enzyme has a molecular mass of approximately 51 kDa and is typically found as a dimer . The enzyme’s activity is optimal at a pH of around 7.0, and it shares a conserved sequence motif with other aminohydrolases and amidohydrolases .
Recombinant human GDA is produced by cloning the GDA gene into an expression vector, such as the pMAL vector, and expressing the protein in a suitable host system like Escherichia coli . The recombinant protein is then purified using affinity chromatography techniques, ensuring high purity and activity.
The recombinant GDA enzyme retains its ability to catalyze the conversion of guanine to xanthine with a Michaelis constant (Km) of approximately 9.5 µM . This value is consistent with the Km values reported for other mammalian guanine deaminases, which range from 4.2 to 15.3 µM .
GDA activity is essential for the proper functioning of the purine metabolism pathway. In cases of xanthine dehydrogenase deficiency, the conversion of guanine to xanthine becomes even more critical, as it helps maintain the balance of purine nucleotides . Additionally, GDA has been implicated in various physiological processes, including neuronal development and function .
Deficiencies or abnormalities in GDA activity can lead to the accumulation of guanine and its derivatives, resulting in various pathological conditions. For example, lead-induced inactivation of GDA activity has been associated with the deposition of guanine crystals in the epiphyseal plate of the femoral head . Moreover, a deficiency in brain GDA activity has been reported in a full-term infant who presented with acute anoxia and died from respiratory distress .
