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Guanine deaminase

Guanine deaminase also known as cypin, guanase, guanine aminase, GAH, and guanine aminohydrolase is an aminohydrolase enzyme which converts guanine to xanthine.[1][2][3] Cypin is a major cytosolic protein that interacts with PSD-95. It promotes localized microtubule assembly in neuronal dendrites.[4]

File:Guanine-xanthine.png
Xanthine synthesis from guanine
References

References

  1. Hitchings GH, Falco EA (Oct 1944). “The Identification of Guanine in Extracts of Girella Nigricans: The Specificity of Guanase”. Proceedings of the National Academy of Sciences of the United States of America. 30 (10): 294–7. doi:10.1073/pnas.30.10.294. PMC 1078714. PMID 16578130.
  2. Kalckar HM (1947). “Differential spectrophotometry of purine compounds by means of specific enzymes; studies of the enzymes of purine metabolism”. J. Biol. Chem. 167 (2): 461–75. PMID 20285041.
  3. Rabinowitz JC, Barker HA (Jan 1956). “Purine fermentation by Clostridium cylindrosporum. II. Purine transformations”. The Journal of Biological Chemistry. 218 (1): 161–73. PMID 13278325.
  4. Firestein BL, Firestein BL, Brenman JE, Aoki C, Sanchez-Perez AM, El-Husseini AE, Bredt DS (1999). “Cypin: a cytosolic regulator of PSD-95 postsynaptic targeting”. Neuron. 24 (3): 659–72. doi:10.1016/S0896-6273(00)81120-4. PMID 10595517.
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