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Measurement of Protein Import Capacity of Skeletal Muscle Mitochondria
Published on: January 7, 2022
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A mitochondrial protein increases glycolytic flux
Sulaiman K Matarneh1, Eric M England1, Tracy L Scheffler1
1Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States.
Meat Science
|July 3, 2017
Summary
Mitochondria contain a protein that accelerates postmortem muscle metabolism, increasing glycogen breakdown and lactate. This may explain the development of acid meat in certain mutated pigs.
Area of Science:
- Biochemistry
- Muscle Physiology
Background:
- Mitochondria play a crucial role in cellular energy metabolism.
- Postmortem muscle metabolism significantly impacts meat quality traits, such as pH and color.
Purpose of the Study:
- To investigate the role of mitochondria in postmortem muscle glycolysis.
- To identify the specific mitochondrial components responsible for altered glycolytic flux.
Main Methods:
- Isolated mitochondria were added to an in vitro glycolysis model.
- Mitochondria were fractionated, and their components were tested in the glycolysis model.
- Perchloric acid was used to deproteinize mitochondrial fractions.
Main Results:
- Mitochondria addition lowered pH and increased glycogen degradation and lactate accumulation.
- Mitochondrial supernatants mimicked the effects of intact mitochondria.
- Deproteinization abolished the effect of mitochondrial supernatants, indicating a protein's role.
Conclusions:
- A mitochondrial protein enhances glycolytic flux in postmortem muscle.
- This protein may contribute to acid meat development in pigs with specific genetic mutations (AMPKγ3R200Q).
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