Intermediary metabolism

Publication date: Available online 13 February 2020Source: Anaesthesia & Intensive Care MedicineAuthor(s): Shilpa Veerappa, Jason McClureAbstractIntermediary metabolism refers to the sum of all intracellular chemical processes by which nutritive material is converted into cellular components. It includes anabolism (synthesis of macromolecules) and catabolism (breakdown of macromolecules). Cellular energy is generated from aerobic oxidation of metabolic fuels (carbohydrates, fats, proteins) derived from digestion of a meal or from breakdown of internal stores. These metabolic fuels are broken down into basic substrates (glucose, amino acids, free fatty acids, glycerol). This is followed by processes that remove electrons (oxidation) from these substrates at high potential and transfer them to substrates at lower potential. It is during these processes that energy is released. Reduced coenzymes (NAD+ and FADH) are intermediate energy storage compounds that aid electron (and energy) transfer from metabolic reactions (glycolysis and Krebs cycle) to the electron transport chain. In the electron transport chain, electrons are transferred through a series of carriers of lower potential and energy released during this is used to form adenosine triphosphate. These electrons finally combine with the end electron acceptor oxygen, to form water. During aerobic metabolism, oxygen is consumed at the end of electron transport chain producing carbon dioxide via Krebs cycle. However, energy c...

Source: Anaesthesia and intensive care medicine - February 13, 2020 Category: Anesthesiology Source Type: research