Fig. 4.

Possible enzyme mechanism of Bacillus amyloliquefaciens TS-Phy (a), and hydrolysis of phytic acid (b). a The hydroxide ion (Wat1) directly attacks the phosphorus atom of phytate phosphorus occupying the Pho1 site. Generally, the role of acid in catalysis can be provided by Wat2, Wat8 or Lys76. This catalysis seems to be severely affected in the hydrolysis of any non-adjacent phosphate group when the Pho2 site is empty. b Only two adjacent matrix phosphate groups can simultaneously occupy the "cleavage site" (Pho1 site) and the "affinity site" (Pho2 site) (Shin et al. 2001)