MYCOLab Ai Logo - gold and army green

Growth Phase-Dependent Changes in the Carbohydrate Metabolism of Penicillium Strains from Diverse Temperature Classes in Response to Cold Stress

Summary

This study examined how three types of fungus respond to cold temperatures by measuring changes in their metabolic enzymes. Researchers exposed young and old fungal cells to cold stress and found that cold temperatures increased enzyme activity in both energy production pathways. Interestingly, the Antarctic psychrotolerant fungus adapted better to cold than the mesophilic fungi, showing that cold-adapted organisms have superior strategies for surviving freezing conditions.

Background

Cold stress induces oxidative stress in aerobic organisms, causing cellular damage and contributing to aging processes. Fungi from extreme environments show varying adaptive responses to temperature changes, but metabolic responses to cold stress in fungi are poorly understood, particularly for polar organisms.

Objective

To investigate the metabolic response to cold stress at the enzyme activity level in three Penicillium strains (one psychrotolerant Antarctic, one mesophilic Antarctic, and one temperate mesophilic) during exponential and stationary growth phases by examining glycolytic and TCA cycle enzyme activities.

Results

Cold stress increased enzymatic activities in both glycolytic and TCA cycle pathways in a stress-level and growth-phase-dependent manner. Mesophilic strains showed more pronounced responses than the psychrotolerant strain. Enzyme activity was consistently lower in stationary-phase cells compared to exponential-phase cells. Temperature reduction to 6°C induced more significant changes than reduction to 15°C.

Conclusion

The psychrotolerant Antarctic strain exhibited superior tolerance to cold stress with less pronounced enzyme activity changes compared to mesophilic strains, indicating that temperature preference is more significant than geographic origin in determining cold stress response. Both growth phases showed metabolic adjustments, with younger cells demonstrating more robust responses than aging cells.
  • Published in:International Journal of Molecular Sciences,
  • Study Type:Experimental Study,
  • Source: PMC12525117, PMID: 41096577
Scroll to Top