Intermediate instability at high temperature leads to low pathway efficiency for an in vitro reconstituted system of gluconeogenesis in Sulfolobus solfataricus

Abstract:

Four enzymes of the gluconeogenic pathway in Sulfolobus solfataricus were purified and kinetically characterized. The enzymes were reconstituted in vitro to quantify the contribution of temperature instability of the pathway intermediates to carbon loss from the system. The reconstituted system, consisting of phosphoglycerate kinase, glyceraldehyde 3-phosphate dehydrogenase, triose phosphate isomerase and the fructose 1,6-bisphosphate aldolase/ phosphatase maintained a constant consumption rate of 3-phosphoglycerate and production of fructose 6-phosphate over a 1 hour period. Cofactors ATP and NADPH were regenerated via pyruvate kinase and glucose dehydrogenase. A mathematical model was constructed on the basis of the kinetics of the purified enzymes and the measured half-life times of the pathway intermediates. The model quantitatively predicted the systems uxes and metabolite concentrations. Relative enzyme concentrations were chosen such that half the carbon in the system was lost due to degradation of the thermolabile intermediates dihydroxyacetone phosphate, glyceraldehyde 3-phosphate and 1,3 bisphosphoglycerate, indicating that intermediate instability at high temperature can significantly affect pathway efficiency. This article is protected by copyright. All rights reserved.

SEEK ID: https://fairdomhub.org/publications/213

PubMed ID: 23865479

Projects: SulfoSys

Journal: FEBS J.

Citation:

Date Published: 20th Jul 2013

Authors: Theresa Kouril, Dominik Esser, Julia Kort, Hans Westerhoff, Bettina Siebers, Jacky Snoep

Help
help Creator
Activity

Views: 3401

Created: 1st Aug 2013 at 13:28

help Attributions

None

Related items

Powered by
Seek new full
(v.1.8.1)
Copyright © 2008 - 2019 The University of Manchester and HITS gGmbH