The pathway of dephosphorylation of myo-inositol hexakisphosphate by phytate-degrading enzymes of different Bacillus spp.
The pathway of dephosphorylation of myo-inositol hexakisphosphate by the phytate-degrading enzymes of Bacillus subtilis 168, Bacillus amyloliquefaciens ATCC 15841, and Bacillus amyloliquefaciens 45 was established using a combination of high-performance ion chromatography analysis and kinetic studies. The data demonstrate that all the Bacillus phytate-degrading enzymes under investigation dephosphorylate myo-inositol hexakisphosphate by sequential removal of phosphate groups via two independent routes; the routes proceed via D-Ins(1,2,4,5,6)P5 to Ins(2,4,5,6)P4 to finally Ins(2,4,6)P3 or D-Ins(2,5,6)P3 and via D-Ins(1,2,4,5,6)P5 to D-Ins(1,2,5,6)P4 to finally D-Ins(1,2,6)P3. The resulting myo-inositol trisphosphate D-Ins(1,2,6)P3 was degraded via D-Ins(2,6)P2 to finally Ins(2)P after prolonged incubation times in combination with increased enzyme concentration.
Greiner
Ralf
R
Centre for Molecular Biology, Federal Research Centre for Nutrition, Haid-und-Neu-Strasse 9, D-76131 Karlsruhe, Germany. ralf.greiner@bfe.uni-karlsruhe.de
Farouk
Adelazim
A
Alminger
Marie Larsson
ML
Carlsson
Nils-Gunnar
NG
D010832:6-Phytase / Q000378:metabolism*; D001407:Bacillus / Q000145:classification / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D010766:Phosphorylation; D010833:Phytic Acid / Q000378:metabolism*
D010833:Phytic Acid; D010832:6-Phytase