Search research articles

Search research articles

Related Experiment Videos

Decrease in yeast glucose-6-phosphate dehydrogenase activity due to oxygen free radicals

I F Dumitru¹, M T Nechifor

¹Department of Enzymology and Biotechnology, University of Bucharest, Romania.

The International Journal of Biochemistry

|February 1, 1994

Summary

This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Spin-spin relaxation times in myocardial hypertrophy induced by endocrine agents in rat.

Magma (New York, N.Y.)·1999

Same author

Influence of isoproterenol-induced cardiac hypertrophy on oxydative myocardial stress.

Romanian journal of physiology : physiological sciences·1995

Same author

Cock seminal plasma acid phosphatase: active site directed inactivation, crystallization and in vitro denaturation-renaturation studies.

The International journal of biochemistry·1994

Same author

Correlations between the activities of semen acid phosphatase and Ca(2+)-dependent ATPase and age in different breeds of cocks.

Comparative biochemistry and physiology. B, Comparative biochemistry·1992

Same author

Study of L-arginine amidinohydrolase from vegetable origin. Purification, crystallization and molecular weight.

Acta vitaminologica et enzymologica·1973

Same author

Stoichiometric relationship between pyridoxal phosphate and alanine aminotransferase apoenzyme.

Enzymologia·1972

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Free radicals from UV radiation and copper acetate significantly reduce glucose-6-phosphate dehydrogenase activity in yeast. This enzyme inactivation correlates with increased malondialdehyde and changes in molecular forms.

Area of Science:

Biochemistry
Enzymology
Yeast Metabolism

Background:

Glucose-6-phosphate dehydrogenase (G6PD) is crucial for cellular redox balance.
Free radicals can damage cellular components, including enzymes.
Saccharomyces cerevisiae is a model organism for studying cellular responses.

Purpose of the Study:

To investigate the effect of free radicals on G6PD activity in Saccharomyces cerevisiae.
To determine the relationship between free radical generation and enzyme inactivation.
To analyze changes in enzyme kinetics and molecular forms.

Main Methods:

Exposure of yeast homogenates to UV radiation and copper acetate as free radical generating systems.
Measurement of G6PD activity and malondialdehyde concentration.

Related Experiment Videos

Enzyme kinetic studies to determine Michaelis constants (Km) for substrates.

Electrophoretic analysis to identify different enzyme molecular forms.

Main Results:

UV radiation and copper acetate significantly diminished G6PD activity.
Enzyme inactivation was proportional to free radical concentration, action time, and irradiation dose.
Decreased catalytic activity correlated with increased malondialdehyde.
Substrate affinity (Km) for NADP halved, while for glucose-6-phosphate remained unchanged.
Electrophoresis revealed the disappearance of one G6PD molecular form.

Conclusions:

Free radicals induce significant inactivation of G6PD in Saccharomyces cerevisiae.
The mechanism of inactivation involves oxidative damage affecting enzyme structure and function.
Changes in Km and molecular forms provide insights into the specific sites of free radical attack.