Table of Contents
- 1 What are chain inhibitors?
- 2 What are inhibitors of oxidative phosphorylation?
- 3 What inhibits the mitochondrial electron transport chain?
- 4 What is an inhibitor and what does it do?
- 5 How do inhibitors inhibit oxidative phosphorylation?
- 6 How does cyanide inhibit the electron transport chain?
- 7 What does Complex 2 do in the electron transport chain?
- 8 What are 3 types of inhibitors?
- 9 How does cyanide affect the electron transport chain?
- 10 What is the electron transport chain simplified?
What are chain inhibitors?
There are a wide range of substances that can inhibit the activity of the electron transport chain. ETC inhibitors include rotenone, antimycin A, cyanide and carbon monoxide. ATP synthase inhibitors include oligomycin A. Uncoupling agents include thermogenin, aspirin and 2,4-dinitrophenol.
What are inhibitors of oxidative phosphorylation?
Inhibitors
| Compounds | Use | Effect on oxidative phosphorylation |
|---|---|---|
| Malonate and oxaloacetate | Poisons | Competitive inhibitors of succinate dehydrogenase (complex II). |
| Antimycin A | Piscicide | Binds to the Qi site of cytochrome c reductase, thereby inhibiting the oxidation of ubiquinol. |
What inhibits the mitochondrial electron transport chain?
Inhibition of the mitochondrial electron transport chain (mETC) induces cell death through generating reactive oxygen species (ROS). Rotenone and TTFA induce ROS production, and the ROS scavenger tiron decreased autophagy and cell death induced by rotenone and TTFA.
What inhibits Complex 2 etc?
Ubiquinone type inhibitors include carboxin and thenoyltrifluoroacetone. Succinate-analogue inhibitors include the synthetic compound malonate as well as the TCA cycle intermediates, malate and oxaloacetate. Indeed, oxaloacetate is one of the most potent inhibitors of Complex II.
What is complex 4 in the electron transport chain?
Complex IV of the electron transport chain, also known as cytochrome c oxidase, is a multiunit structure that functions to transfer electrons form cytochrome c to oxygen and in the process form water and help generate a proton gradient. CuB associates with heme A-3 to help reduce oxygen into water.
What is an inhibitor and what does it do?
Inhibitors. Enzyme inhibitors are compounds which modify the catalytic properties of the enzyme and, therefore, slow down the reaction rate, or in some cases, even stop the catalysis. Such inhibitors work by blocking or distorting the active site.
How do inhibitors inhibit oxidative phosphorylation?
Oligomycin B and DCCD inhibit oxidative phosphorylation by blocking the proton pore of the ATP synthase.
How does cyanide inhibit the electron transport chain?
Cyanide poisons the mitochondrial electron transport chain within cells and renders the body unable to derive energy (adenosine triphosphate—ATP) from oxygen. Specifically, it binds to the a3 portion (complex IV) of cytochrome oxidase and prevents cells from using oxygen, causing rapid death.
What happens when complex 4 is inhibited?
The blocklock of complex IV by cyanide depletes ATP culminating in cell death. Thus, cellular respiration is inhibited, as well as ATP production, in essence depriving the cells, tissue, and, ultimately, the whole body of oxygen.
What is complex 3 electron transport chain?
Complex III of the electron transport chain, also known as Q-cytochrome c oxidoreductase or simply cytochrome reductase, is a multi-subunit structure that functions to accept electrons from ubiquinol and transfer them onto another electron carrier called cytochrome c.
What does Complex 2 do in the electron transport chain?
Complex II of the electron transport chain, also known as succinate reductase, is involved in the citric acid cycle. It contains the enzyme called succinate dehydrogenase that was used by the citric acid cycle to transform succinate into fumarate and in the process form FADH2.
What are 3 types of inhibitors?
There are three kinds of reversible inhibitors: competitive, noncompetitive/mixed, and uncompetitive inhibitors. Competitive inhibitors, as the name suggests, compete with substrates to bind to the enzyme at the same time. The inhibitor has an affinity for the active site of an enzyme where the substrate also binds to.
How does cyanide affect the electron transport chain?
Cyanide binds to the iron inside this protein and prevents electron transportation to oxygen from cytochrome c oxidase . Consequently, the cell is no longer able to aerobically produce ATP for energy. There is a disruption of the electron transport chain.
What are the steps of electron transport chain?
The entire electron transport chain involves four major membrane proteins that work together to accomplish ATP synthesis. The steps are complex 1, complex 2, complex 3, and complex 4. Complex one is often referred to as NADH dehydrogenase, and the reason you need to know that term is because it’s testable in the MCAT.
What is the role of electron transport chain in cellular respiration?
Thus, the electron transport chain is a crucial cellular machinery for its major role in extracting energy via redox reactions in cellular respiration as well as in photosynthesis. The electron transport chain is comprised chiefly of electron donors and acceptors.
What is the electron transport chain simplified?
The Electron Transport Chain Steps Simplified. The electron transport chain is the final and most important step of cellular respiration. While Glycolysis and the Citric Acid Cycle make the necessary precursors, the electron transport chain is where a majority of the ATP is created.