Vanadate Influence on Metabolism of Sugar Phosphates in Fungus Phycomyces blakesleeanus

The biological and chemical basis of vanadium action in fungi is relatively poorly understood. In the present study, we investigate the influence of vanadate (V(5+)) on phosphate metabolism of Phycomyces blakesleeanus. Addition of V(5+) caused increase of sugar phosphates signal intensities in (31)P NMR spectra in vivo. HPLC analysis of mycelial phosphate extracts demonstrated increased concentrations of glucose 6 phosphate, fructose 6 phosphate, fructose 1, 6 phosphate and glucose 1 phosphate after V(5+) treatment. Influence of V(5+) on the levels of fructose 2, 6 phosphate, glucosamine 6 phosphate and glucose 1, 6 phosphate (HPLC), and polyphosphates, UDPG and ATP ((31)P NMR) was also established. Increase of sugar phosphates content was not observed after addition of vanadyl (V(4+)), indicating that only vanadate influences its metabolism. Obtained results from in vivo experiments indicate catalytic/inhibitory vanadate action on enzymes involved in reactions of glycolysis and glycogenesis i.e., phosphoglucomutase, phosphofructokinase and glycogen phosphorylase in filamentous fungi.