X-ray Crystallography and Electron Paramagnetic Resonance Spectroscopy Reveal Active Site Rearrangement of Cold-Adapted Inorganic Pyrophosphatase.

ABSTRACT: Inorganic pyrophosphatase (PPase) catalyses the hydrolysis reaction of inorganic pyrophosphate to phosphates. Our previous studies showed that manganese (Mn) activated PPase from the psychrophilic bacterium Shewanella sp. AS-11 (Mn-Sh-PPase) has a characteristic temperature dependence of the activity with an optimum at 5 °C. Here we report the X-ray crystallography and electron paramagnetic resonance (EPR) spectroscopy structural analyses of Sh-PPase in the absence and presence of substrate analogues. We successfully determined the crystal structure of Mn-Sh-PPase without substrate and Mg-activated Sh-PPase (Mg-Sh-PPase) complexed with substrate analogue (imidodiphosphate; PNP). Crystallographic studies revealed a bridged water placed at a distance from the di-Mn centre in Mn-Sh-PPase with

SUBMITTER: Horitani M 

PROVIDER: S-EPMC7062746 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature