Pyruvate dehydrogenase complex

Contents in brief: What is the pyruvate dehydrogenase complex? Coenzymes of the pyruvate dehydrogenase complex Where is the pyruvate dehydrogenase complex located? Functions of the pyruvate dehydrogenase complex Other sources of acetyl-CoA Sources of pyruvate Mitochondrial pyruvate transport Structure of the pyruvate dehydrogenase complex Structure of pyruvate dehydrogenase or E1 What is the function of […]

Glycolysis

Contents in brief: What is glycolysis? Glycolysis: the first metabolic pathway to be elucidated Why is glycolysis so important? The steps of glycolysis Reaction 1: glucose phosphorylation to glucose 6-phosphate The importance of glucose phosphorylation Other possible fates of glucose 6-phosphate Reaction 2: isomerization of glucose 6-phosphate to fructose 6-phosphate Reaction 3: phosphorylation of fructose […]

Gluconeogenesis

Contents in brief: What is gluconeogenesis? Why is gluconeogenesis important? Where does gluconeogenesis occur? Irreversible steps of gluconeogenesis From pyruvate to phosphoenolpyruvate Phosphoenolpyruvate precursor: pyruvate or alanine Phosphoenolpyruvate precursor: lactate From fructose 1,6-bisphosphate to fructose 6-phosphate From glucose 6-phosphate to glucose Gluconeogenesis: energetically expensive Coordinated regulation of gluconeogenesis and glycolysis Regulation of gluconeogenesis Pyruvate carboxylase […]

Cori cycle: definition, function, biochemistry, involved tissues

Contents in brief: What is the Cori cycle? Where does the Cori cycle occur? The steps of the Cori cycle Lactate dehydrogenase Other metabolic fates of lactate Energy cost of the glucose-lactate cycle Is the Cori cycle a futile cycle? The Cori cycle and glucose-alanine cycle References What is the Cori cycle? The Cori cycle, […]

Gluten: definition, structure, properties, wheat, cereal list

Contents in brief: What is gluten? Cereals containing gluten Cereal grain proteins Wheat gluten proteins Gliadins: extensibility and viscosity Glutenins: elasticity and toughness Properties of wheat gluten Gluten-free cereals Oats and gluten References What is gluten? Gluten is not a single protein but a mixture of cereal proteins, about 80% of its dry weight (for […]

Digestion of starch and alpha-amylase

Factors affecting relationship between starch and alpha-amylase Amylose and amylopectin, the two families of homopolysaccharides constituting starch, during their biosynthesis within vegetable cells, are deposited in highly organized particles called granules. Granules have a partially crystalline structure and diameter ranging from 3 to 300 µm. The access of the alpha-amylase, the enzyme that catalyzes the […]

Maltodextrin, fructose and endurance sports

Carbohydrate ingestion can improve endurance capacity and performance. The ingestion of different types of carbohydrates, which use different intestinal transporters, can: increase total carbohydrate absorption; increase exogenous carbohydrate oxidation; and therefore improve performance. Glucose and fructose When a mixture of glucose and fructose is ingested (in the analyzed literature, respectively 1.2 and 0.6 g/min, ratio 2:1, for […]

Prolonged exercise and carbohydrate ingestion

During prolonged exercise (>90 min), like marathon, Ironman, cross-country skiing, road cycling or open water swimming, the effects of supplementary carbohydrates on performance are mainly metabolic rather than central and include: the provision of an additional muscle fuel source when glycogen stores become depleted; muscle glycogen sparing; the prevention of low blood glucose concentrations. How many carbohydrates should […]

Carbohydrate ingestion during exercise of relatively short duration and high intensity

Intermittent high intensity exercise and carbohydrate ingestion Carbohydrate ingestion during intermittent high intensity or prolonged (>90 min) sub-maximal exercise can: increase exercise capacity; improve exercise performance; postpone fatigue. The intake of very small amounts of carbohydrates or carbohydrate mouth rinsing (for example with a 6% maltodextrin solution) may improve exercise performance by 2-3% when the […]

Hydration before endurance sports

Dehydration and endurance sports In endurance sports, like Ironman, open water swimming, road cycling, marathon, or cross-country skiing, the most likely contributors to fatigue are dehydration and carbohydrate (especially liver and muscle glycogen) depletion. Pre-hydration Due to sweat loss needed to dissipate the heat generated during exercise, dehydration can compromise exercise performance. It is important to […]

Scroll Up