Pathway of dephosphorylation of myo-inositol hexakisphosphate by phytases of legume seeds.
Using a combination of high-performance ion chromatography analysis and kinetic studies, the pathway of dephosphorylation of myo-inositol hexakisphosphate by the phytases purified from faba bean and lupine seeds, respectively, was established. The data demonstrate that the legume seed phytases under investigation dephosphorylate myo-inositol hexakisphosphate in a stereospecific way. The phytase from faba bean seeds and the phytase LP2 from lupine seeds degrade phytate by sequential removal of phosphate groups via D-Ins(1,2,3,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), and D-Ins(1,2)P(2) to finally Ins(2)P, whereas the phytases LP11 and LP12 from lupine seeds generate the final degradation product Ins(2)P via D-Ins(1,2,4,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), and D-Ins(1,2)P(2).
Greiner
Ralf
R
Centre for Molecular Biology, Federal Research Centre for Nutrition, Haid-und-Neu-Strasse 9, D-76131 Karlsruhe, Germany.
Larsson Alminger
Marie
M
Carlsson
Nils-Gunnar
NG
Muzquiz
Mercedes
M
Burbano
Carmen
C
Cuadrado
Carmen
C
Pedrosa
Mercedes M
MM
Goyoaga
Carmen
C
D010832:6-Phytase / Q000378:metabolism*; D007887:Fabaceae / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D010766:Phosphorylation; D010833:Phytic Acid / Q000378:metabolism*; D012639:Seeds / Q000201:enzymology*
D010833:Phytic Acid; D010832:6-Phytase