Lipid Anabolism and Fatty Acid Biosynthesis

This collection of flashcards covers essential vocabulary and concepts related to lipid anabolism, fatty acid biosynthesis, and related metabolic processes.

Lipid Anabolism

The process of synthesizing lipids from smaller units such as acetyl CoA.

Glycogen

A stored form of glucose in the body, primarily found in the liver and muscle.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, releasing energy.

Acetyl CoA

A central metabolite in energy metabolism; derived from carbohydrates and fats.

Fatty Acids

Carboxylic acids with long aliphatic chains, which can be saturated or unsaturated.

TAGs (Triacylglycerols)

Fat molecules composed of glycerol and three fatty acids.

Cytosol

The fluid portion of the cytoplasm in which cellular processes occur.

NADPH

A reducing agent that provides the electrons needed for biosynthetic reactions.

Malonyl CoA

A key intermediate in fatty acid biosynthesis, formed from acetyl CoA.

ACP (Acyl Carrier Protein)

A protein that carries fatty acyl chains during fatty acid synthesis.

β-Ketoacyl-ACP synthase

An enzyme that catalyzes the condensation of acetyl ACP and malonyl ACP.

Enoyl-ACP reductase

An enzyme involved in the reduction step of fatty acid biosynthesis.

Thioesterase

An enzyme that cleaves fatty acyl-ACP to release fatty acids.

Palmitate

The end product of mammalian fatty acid biosynthesis; a C16 saturated fatty acid.

Desaturation

The process of introducing double bonds into fatty acids.

Elongation

The process of adding two-carbon units to fatty acid chains.

Cholesterol

A type of lipid essential for cell membrane structure and function.

HMG-CoA reductase

A key regulatory enzyme in cholesterol biosynthesis, targeted by statins.

Squalene

A precursor in the biosynthetic pathway for cholesterol.

Mevalonate

An intermediate in the cholesterol synthesis pathway.

Insulin's Role

Stimulates the biosynthesis of lipids and regulates glucose uptake.

Glucagon's Role

Promotes lipolysis and regulates energy balance when glucose levels are low.

Feedback Inhibition

A regulatory mechanism where the end product inhibits an earlier step.

Acetyl-CoA carboxylase

An enzyme that catalyzes the carboxylation of acetyl CoA to malonyl CoA.

Fatty Acid Synthase Complex

A multi-enzyme complex that catalyzes fatty acid synthesis.

Carboxylation

The addition of a carboxyl group to a molecule, critical in fatty acid synthesis.

Condensation Reaction

A chemical reaction where two molecules combine to form a larger molecule with the release of a small molecule.

Key Steps of Fatty Acid Biosynthesis

Include production, carboxylation, attachment of CoA, condensation, reduction, dehydration.

Diglyceride acyl transferase

An enzyme that aids in the conversion of phosphatidate to diacylglycerol.

Glycerol 3-P-acyl transferase

An enzyme that catalyzes the formation of TAGs from glycerol 3-phosphate.

Endoplasmic Reticulum

Cellular membrane system where lipid biosynthesis occurs.

Hydroxybutyryl ACP

An intermediate formed during the reduction step of fatty acid synthesis.

Linoleate

An essential fatty acid with the chemical formula C18H32O2.

α-Linoleate

A polyunsaturated fatty acid that is essential in human nutrition.

Polyunsaturated Fatty Acids (PUFAs)

Fatty acids that contain multiple double bonds.

Eicosatrienoate

A 20-carbon fatty acid with three double bonds.

Arachidonate

A polyunsaturated fatty acid important in signaling pathways.

Regulation of Cholesterol Synthesis

Involves multiple steps and is influenced by various hormones and nutritional states.

Palmitoleate

A 16-carbon unsaturated fatty acid formed from palmitate.

Oleate

An unsaturated fatty acid derived from oleic acid, commonly found in olive oil.

Acetyl CoA transport

Transported as citrate from mitochondria to cytosol for fatty acid synthesis.

Phosphatase

An enzyme that removes phosphate groups from molecules.

NADP+

Nicotinamide adenine dinucleotide phosphate, an oxidized coenzyme.

ATP

Adenosine triphosphate, the energy currency of the cell.

Pyruvate

The end product of glycolysis, which can be converted into acetyl CoA.

Citrate lyase

An enzyme that cleaves citrate to regenerate acetyl CoA in the cytosol.

Acetyl CoA-ACP transacetylase

An enzyme involved in transferring acetyl groups to ACP.