TY - JOUR
T1 - Can yeast glycolysis be understood in terms of in vitro kinetics of the constituent enxymes? Testing biochemistry.
AU - Teusink, B.
AU - Passarge, J.R.
AU - Reijenga, C.A.
AU - Esgalhado, M.E.L.M.
AU - van der Weijden, C.C.
AU - Schepper, M.
AU - Walsh, M.C.
AU - Bakker, B.M.
AU - van Dam, K.
AU - Westerhoff, H.V.
AU - Snoep, J.L.
PY - 2000
Y1 - 2000
N2 - This paper examines whether the in vivo behavior of yeast glycolysis can be understood in terms of the in vitro kinetic properties of the constituent enzymes. In nongrowing, anaerobic, compressed Saccharomyces cerevisiae the values of the kinetic parameters of most glycolytic enzymes were determined. For the other enzymes appropriate literature values were collected. By inserting these values into a kinetic model for glycolysis, fluxes and metabolites were calculated. Under the same conditions fluxes and metabolite levels were measured. In our first model, branch reactions were ignored. This model failed to reach the stable steady state that was observed in the experimental flux measurements. Introduction of branches towards trehalose, glycogen, glycerol and succinate did allow such a steady state. The predictions of this branched model were compared with the empirical behavior. Half of the enzymes matched their predicted flux in vivo within a factor of 2. For the other enzymes it was calculated what deviation between in vivo and in vitro kinetic characteristics could explain the discrepancy between in vitro rate and in vivo flux.
AB - This paper examines whether the in vivo behavior of yeast glycolysis can be understood in terms of the in vitro kinetic properties of the constituent enzymes. In nongrowing, anaerobic, compressed Saccharomyces cerevisiae the values of the kinetic parameters of most glycolytic enzymes were determined. For the other enzymes appropriate literature values were collected. By inserting these values into a kinetic model for glycolysis, fluxes and metabolites were calculated. Under the same conditions fluxes and metabolite levels were measured. In our first model, branch reactions were ignored. This model failed to reach the stable steady state that was observed in the experimental flux measurements. Introduction of branches towards trehalose, glycogen, glycerol and succinate did allow such a steady state. The predictions of this branched model were compared with the empirical behavior. Half of the enzymes matched their predicted flux in vivo within a factor of 2. For the other enzymes it was calculated what deviation between in vivo and in vitro kinetic characteristics could explain the discrepancy between in vitro rate and in vivo flux.
U2 - 10.1046/j.1432-1327.2000.01527.x
DO - 10.1046/j.1432-1327.2000.01527.x
M3 - Article
SN - 0014-2956
VL - 267
SP - 5313
EP - 5329
JO - European Journal of Biochemistry
JF - European Journal of Biochemistry
ER -