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Metabolic channeling: predictions, deductions, and evidence
Vidhi Pareek1, Zhou Sha2, Jingxuan He2
1Huck Institutes of Life Sciences, Pennsylvania State University, University Park, PA 16802, USA.
Molecular Cell
|September 21, 2021
Summary
Metabolic channeling enhances cellular pathway efficiency by directly passing enzyme products between enzymes. This mechanism, seen in molecular tunnels and metabolons like the purinosome, prevents intermediate diffusion and interference.
Area of Science:
- Biochemistry
- Cell Biology
- Metabolic Engineering
Background:
- Cellular metabolism involves complex, interconnected enzyme-catalyzed pathways.
- Efficient operation of these networks requires mechanisms to maximize catalytic efficiency and minimize interference.
Purpose of the Study:
- To present evidence supporting the concept of metabolic channeling.
- To explore various mechanisms of metabolic channeling, from molecular tunnels to metabolons.
Main Methods:
- Review of existing literature and experimental evidence.
- Analysis of enzyme structures and multi-enzyme complexes.
- Discussion of metabolon assembly and function, including the purinosome.
Main Results:
- Metabolic channeling can occur via physical molecular tunnels.
- Multi-enzyme complexes and metabolons facilitate channeling through electrostatics, enclosures, or clustering.
- Reversibly assembled metabolons, such as the purinosome, offer advantages in pathway regulation.
Conclusions:
- Metabolic channeling is a crucial strategy for efficient and controlled cellular metabolism.
- Diverse structural and organizational strategies contribute to metabolic channeling.
- The purinosome exemplifies the functional benefits of dynamic metabolon assembly.
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