In Saccharomyces cerevisiae , the effect of H 2 O 2 on ATP, but not on glyceraldehyde-3-phosphate dehydrogenase, depends on the glucose concentration

Abstract

As has been previously shown, Saccharomyces cerevisiae grown in 2% or 0.025% glucose uses this carbohydrate by the fermentative or oxidative pathways, respectively. Depending on the glucose concentration in the medium, the effect of the addition of H2O2 on the level of ATP and on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity differed. In the presence of 2% glucose, ATP and GAPDH decreased sharply during the first few minutes of treatment, whereas in the presence of 0.025% glucose, GAPDH activity decreased similarly, but the ATP level remained practically unchanged. The addition of 3 mM glutathione to the culture media prevented the depletion of ATP levels and GAPDH activity in the presence of H2O2. Catalase and superoxide dismutase activities did not vary significantly when yeast cells were grown either in 2% or in 0.025% glucose.

Revised procedures for yeast metabolites extraction: application to a glucose pulse to carbon‐limited yeast cultures, which reveals a transient activation of the purine salvage pathway

“…Osorio and collaborators (2003) also reported a dramatic increase of inosine concomitant with a decrease of ATP following addition of H 2 O 2 to exponentially growing yeast cells on glucose. However, whereas the effect of this oxidative agent was explained by a direct inhibition of glyceraldehyde 3‐P dehydrogenase (Osorio et al , 2004), we did not find any change in the activity of this enzyme upon addition of glucose to our carbon‐limited cultures (data not shown), suggesting that while both treatments led to the same metabolic consequence, the mechanism is likely not the same between glucose and H 2 O 2 .…”

Fungicidal Drugs Induce a Common Oxidative-Damage Cellular Death Pathway

“…We found that the AF treatments elevated the AMP/ATP ratio by between 4- and 24-fold (Figure 3E), through a large drop in ATP levels and a proportional rise in AMP levels. ATP levels are normally static, but can change dramatically under severe stress conditions that induce necrosis (Henriquez et al, 2008; Osorio et al, 2004). Our results suggest that fungicide-stimulated sugar production induces a necrosis-like rapid consumption of ATP.…”

“…These similarities include a collapse of ATP levels (Osorio et al, 2004), mitochondrial dysfunction that leads to the production of ROS (Breitenbach et al, 2005), and a central role played by the RAS/PKA pathway (Estruch, 2000). It is likely that AFs cause cellular damage that mirrors the effects of osmotic, heat and alcohol stress, leading to the induction of stress-related pathways.…”

Glucose activates H+-ATPase in kidney epithelial cells

“…Recently, other studies have shown that ATP level remained practically unchanged when yeast cells were grown in either 2% or 0.025% glucose (44). Krauss et al (28) demonstrated that under physiological conditions, hyperglycemia-induced mitochondrial superoxide production activates uncoupling protein 2, which decreases the ATP-to-ADP ratio.…”