26 Gluconeogenesis

A set of 30 vocabulary flashcards based on the lecture notes about gluconeogenesis, including definitions and key concepts.

Gluconeogenesis

The process of synthesizing glucose from non-carbohydrate precursors.

Pyruvate Carboxylase

An enzyme that converts pyruvate into oxaloacetate in the mitochondria.

PEPCK

Phosphoenolpyruvate carboxykinase, an enzyme that converts oxaloacetate into phosphoenolpyruvate.

Fructose-1,6-bisphosphatase

An enzyme involved in gluconeogenesis that catalyzes the conversion of fructose-1,6-bisphosphate to fructose-6-phosphate.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, producing ATP.

Fructose-2,6-bisphosphate

A key regulator of gluconeogenesis and glycolysis.

Bifunctional enzyme

An enzyme that has two different activities, such as PFK-2/FBPase-2.

Cori Cycle

The process by which lactate produced in muscles is transported to the liver and converted back to glucose.

Hexokinase IV (Glucokinase)

An enzyme that helps in the phosphorylation of glucose in the liver and pancreas.

Glucose-6-phosphatase

An enzyme that converts glucose-6-phosphate into glucose, allowing for its export from the cell.

Acetyl-CoA

A molecule that plays a central role in metabolism and acts as an allosteric regulator of pyruvate carboxylase.

Biotin

A vitamin (B7) that serves as a prosthetic group for carboxylation reactions.

NADH

Nicotinamide adenine dinucleotide, a coenzyme that carries electrons during metabolic reactions.

GTP

Guanosine triphosphate, a molecule that provides energy for biochemical reactions.

ATP

Adenosine triphosphate, the primary energy carrier in cells.

Liver

The primary organ where gluconeogenesis occurs.

Kidney

An organ that participates to a lesser extent in gluconeogenesis.

Fructose-1,6-bisphosphate

An intermediate in glycolysis and gluconeogenesis that is regulated by FBPase-1 and PFK-1.

Kinetic control

Regulation of a reaction based on the concentration of reactants and products.

Amino acids

Building blocks of proteins that can serve as precursors for gluconeogenesis.

Lactate

A product of anaerobic metabolism that can be converted back to glucose.

Reactive free energy drops

Changes in free energy that drive metabolic reactions in glycolysis and gluconeogenesis.

Glycogen

A stored form of glucose that can be mobilized during fasting.

Malate-aspartate shuttle

A transport system that transfers electrons across the mitochondrial membrane.

Feed-forward activation

A regulatory mechanism where the product of one enzyme stimulates the activity of another enzyme.

Hormonal regulation

Control of metabolic pathways by hormones such as insulin and glucagon.

Insulin

A hormone that promotes glucose uptake and storage in the fed state.

Glucagon

A hormone that promotes glucose production and release in the fasted state.

PKA (Protein Kinase A)

An enzyme that regulates various cellular processes in response to glucagon signaling.

PP1 (Protein Phosphatase 1)

An enzyme that dephosphorylates proteins, often activated by insulin signaling.

Fasted state

A metabolic state where glucose levels are low and gluconeogenesis is increased.

Fed state

A metabolic state where glucose levels are high and glycolysis is favored.

Reciprocal regulation

The coordination of opposing metabolic pathways such as glycolysis and gluconeogenesis.

Bypass reactions

Specific steps in gluconeogenesis that replace irreversible steps in glycolysis.

Reducing equivalents

Electrons or hydrogens transferred in redox reactions during metabolic processes.