22 oxidative phosphorylation

These flashcards cover key vocabulary and concepts surrounding oxidative phosphorylation, ATP synthesis, and the relevant biochemical processes discussed in the lecture.

Oxidative phosphorylation

The process in aerobic respiration that generates ATP through the electron transport chain and ATP synthase.

Electron transport chain

A series of protein complexes that transfer electrons from electron donors to electron acceptors via redox reactions.

ATP synthase

An enzyme that synthesizes ATP from ADP and inorganic phosphate using the energy from a proton gradient.

Proton gradient

A difference in proton concentration across a membrane, created by the electron transport chain, which is used to generate ATP.

Protonmotive force

The energy stored in the form of an electrochemical gradient of protons across a membrane.

Supercomplexes

Associations of respiratory chain complexes in the inner mitochondrial membrane forming 'respirasomes'.

ΔG

Change in Gibbs free energy, important for understanding spontaneity in biochemical reactions.

NADH

A coenzyme that carries electrons to the electron transport chain and contributes to the proton gradient.

FADH2

A molecule that acts as an electron donor in the electron transport chain, generating a proton gradient.

Endergonic reaction

A reaction that requires energy input, such as ATP synthesis.

Exergonic reaction

A reaction that releases energy, such as the transport of protons down an electrochemical gradient.

Oligomycin

An antibiotic that inhibits ATP synthase, preventing ATP production.

Brown adipose tissue

A type of fat tissue that generates heat through regulated uncoupling of oxidative phosphorylation.

Uncoupling protein I (UCP-1)

A protein in brown fat that allows protons to re-enter the mitochondrial matrix, dissipating energy as heat.

Dinitrophenol

A chemical that uncouples oxidative phosphorylation, causing energy from electron transport to be lost as heat.

Thermodynamically favorable

A condition that allows a process to occur spontaneously due to a negative change in free energy.

ATP yield

The amount of ATP produced from metabolic processes such as aerobic respiration.

Hydrogen ion (H+)

A proton that plays a key role in creating the proton gradient used for ATP synthesis.

Catabolic pathways

Metabolic pathways that break down molecules to produce energy.

Cyclic rotation

The mechanism by which the γ subunit of ATP synthase rotates to facilitate ATP production.

Protonation

The addition of a proton to a molecule, critical in the function of ATP synthase.

Matrix

The innermost compartment of the mitochondria, where metabolic reactions occur.

Intermembrane space

The space between the inner and outer mitochondrial membranes, where protons are accumulated.

Stoichiometric coupling

The direct relationship between the consumption of oxygen and ATP synthesis.

Respiratory control

The regulation of respiration based on the availability of substrates like ADP.

Half-channels

Structural components of ATP synthase that allow protons to flow across the membrane.

Lipid bilayer

The double layer of phospholipids that makes up cellular membranes.

Mitochondrial envelope

The double membrane surrounding mitochondria, consisting of an outer and inner membrane.

Glutamate

An amino acid that plays a critical role in the function of ATP synthase by participating in protonation and re-ionization.

Catalytic domains

The specific regions of enzymes that facilitate the conversion of substrates to products.

Substrate-level phosphorylation

The immediate generation of ATP in metabolic pathways without the involvement of electron transport.

Metabolic flux

The rate at which metabolites flow through a metabolic pathway.

Acetyl-CoA

A central molecule in metabolism that feeds into the citric acid cycle.

Citric acid cycle

A series of enzymatic reactions that produces energy through the oxidation of acetyl-CoA.

Coupling

The linking of two biochemical processes, such as electron transport and ATP synthesis.