IMP‐GMP 5′‐Nucleotidase from Rat Brain: Activation by Polyphosphates

@article{Marques1998IMPGMP5F,
  title={IMP‐GMP 5′‐Nucleotidase from Rat Brain: Activation by Polyphosphates},
  author={A. F. Marques and N. Teixeira and C. Gambaretto and A. Sillero and M. G. G{\"u}nther Sillero},
  journal={Journal of Neurochemistry},
  year={1998},
  volume={71}
}
Abstract: IMP‐GMP 5′‐nucleotidase has been purified to homogeneity from total rat brain extracts. This preparation showed a unique band (Mr 54,000 ± 1,509) in sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. The enzyme presented the following properties: optimal pH value, 6.5–6.8; relative velocity measured in the presence of MgCl2, MnCl2, CoCl2, and NiCl2 (2 mM), 100, 60, 11, and <1, respectively; preferred substrates, IMP and GMP; and activation constant (Ka) found for Ap4A, Ap5A… Expand
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