Effect of a nonmetabolizable analog of fructose-1,6-bisphosphate on glycolysis and ethanol production in strains of Saccharomyces cerevisiae and Escherichia coli.
Fructose-1,6-bisphosphate (F-1,6-P2) is an allosteric activator of two key enzymes of glycolysis: phosphofructokinase and pyruvate kinase. Regulation of glycolysis in a wild-type Saccharomyces cerevisiae and a recombinant Escherichia coli by a dead-end structural analog of F-1,6-P2 was studied. 2,5-Anhydromannitol (2,5-AM), a structural analog of beta-d-fructose, was used. On being taken up by the cells, 2,5-AM was converted into its monophosphate and diphosphate by the enzymes of the glycolytic pathway. The final product, 2,5-anhydromannitol-1,6-bisphosphate, could not be metabolized further and, therefore, accumulated inside the cells. Glucose and fructose were used as substrates. It was found that 2,5-AM at concentrations of 1 mM or less did not have any effect on either substrate consumption or ethanol production. At concentrations of 2,5-AM of 2.5 mM or greater, significant inhibition of both glucose and fructose was observed, with fructose inhibition much more severe. We discuss the possible mechanisms of glycolysis inhibition by 2,5-AM at high concentrations and the regulation of glycolysis by this compound.
Nghiem
Nhuan P
NP
Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA. Nghiem@ARS.USDA.GOV
Cofer
Timothy M
TM
D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D004926:Escherichia coli / Q000378:metabolism*; D000431:Ethanol / Q000737:chemistry*; D005285:Fermentation; D005632:Fructose / Q000737:chemistry; D006597:Fructose-Bisphosphatase / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry / Q000378:metabolism; D006019:Glycolysis; D008353:Mannitol / Q000031:analogs & derivatives / Q000737:chemistry; D008956:Models, Chemical; D011770:Pyruvate Kinase / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013997:Time Factors
D011994:Recombinant Proteins; D005632:Fructose; D000431:Ethanol; D008353:Mannitol; C031765:2,5-anhydromannitol; D011770:Pyruvate Kinase; D006597:Fructose-Bisphosphatase; D005947:Glucose