The article "The Multifaceted Contributions of Mitochondria to Cellular Metabolism" by Jessica B. Spinelli and Marcia C. Haigis reviews the diverse roles of mitochondria in cellular metabolism. Mitochondria are not only the primary source of ATP through oxidative phosphorylation but also play crucial roles in biosynthesis, redox homeostasis, and waste management. They generate metabolic precursors for macromolecules, maintain redox balance through the production and consumption of reactive oxygen species (ROS), and manage metabolic waste products such as lactate and ammonia. The authors highlight how these functions are essential in both normal physiological processes and disease states, emphasizing the importance of understanding mitochondrial metabolism for therapeutic interventions. The review covers key metabolic pathways, including pyruvate, glutamine, branched-chain amino acids (BCAAs), fatty acid oxidation, nucleotide synthesis, citrate, amino acid synthesis, and heme metabolism. It also discusses the role of mitochondrial transporters in coordinating metabolic flux and the impact of metabolic by-products like ROS and hydrogen sulfide on cellular function. The authors conclude by emphasizing the need for further research to identify transporters that enable metabolic compartmentalization and to understand the physiological contributions of mitochondria in various cellular contexts.The article "The Multifaceted Contributions of Mitochondria to Cellular Metabolism" by Jessica B. Spinelli and Marcia C. Haigis reviews the diverse roles of mitochondria in cellular metabolism. Mitochondria are not only the primary source of ATP through oxidative phosphorylation but also play crucial roles in biosynthesis, redox homeostasis, and waste management. They generate metabolic precursors for macromolecules, maintain redox balance through the production and consumption of reactive oxygen species (ROS), and manage metabolic waste products such as lactate and ammonia. The authors highlight how these functions are essential in both normal physiological processes and disease states, emphasizing the importance of understanding mitochondrial metabolism for therapeutic interventions. The review covers key metabolic pathways, including pyruvate, glutamine, branched-chain amino acids (BCAAs), fatty acid oxidation, nucleotide synthesis, citrate, amino acid synthesis, and heme metabolism. It also discusses the role of mitochondrial transporters in coordinating metabolic flux and the impact of metabolic by-products like ROS and hydrogen sulfide on cellular function. The authors conclude by emphasizing the need for further research to identify transporters that enable metabolic compartmentalization and to understand the physiological contributions of mitochondria in various cellular contexts.