Article

The ATP paradox is the expression of an economizing fuel mechanism.

Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain.
Journal of Biological Chemistry (impact factor: 4.77). 01/2005; 279(53):55372-5. DOI:10.1074/jbc.M410479200 pp.55372-5
Source: PubMed

ABSTRACT The strong negative correlation between glycolytic flux and intracellular ATP concentration observed in yeast has long been an intriguing and counterintuitive phenomenon, which has been referred to as the ATP paradox. Herein, using principles of irreversible thermodynamics it was shown that if the ATP-consuming pathways are more sensitive to extracellular glucose than glycolysis, then upon glucose addition glycolysis performance can switch from an efficient working regime to a dissipative regime, and vice versa, depending on glucose availability. The efficient regime represents a good compromise between high output power and low dissipation, whereas the dissipative working regime offers a higher output power although at a high glucose cost. The physiological and evolutionary implications of this switch strategy are discussed.

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Keywords

ATP paradox
 
ATP-consuming pathways
 
dissipative
 
dissipative regime
 
efficient
 
efficient regime
 
extracellular glucose
 
glucose addition glycolysis performance
 
glucose availability
 
glucose cost
 
glycolysis
 
glycolytic flux
 
higher output power
 
intriguing
 
irreversible thermodynamics
 
low dissipation
 
output power
 
sensitive
 
strong negative correlation
 
switch strategy