Binding of substrate at the effector site of pyrophosphatase increases the rate of its hydrolysis at the active site

@article{Sitnik2007BindingOS,
  title={Binding of substrate at the effector site of pyrophosphatase increases the rate of its hydrolysis at the active site},
  author={Tatyana S Sitnik and Svetlana M. Avaeva},
  journal={Biochemistry (Moscow)},
  year={2007},
  volume={72},
  pages={68-76}
}
It is shown that in addition to the active site, each subunit of Escherichia coli inorganic pyrophosphatase (E-PPase) contains an extra binding site for the substrate magnesium pyrophosphate or its non-hydrolyzable analog magnesium methylenediphosphonate. The occupancy of the extra site stimulates the substrate conversion. Binding affinity of this site decreased or disappeared upon the conversion of E-PPase into a trimeric form or introduction of point mutations. However, when the slowly… 

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Fluorescent and Colorimetric Dual-Readout Assay for Inorganic Pyrophosphatase with Cu(2+)-Triggered Oxidation of o-Phenylenediamine.

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