Science

What is the function of cytochrome b6f?

By: Matt SniderUpdated: February 22, 2021

Categories

Site Statistics

  • Questions
    94,481
  • Answers
    1,984,101
  • Categories
    21
  • Last Updated
    September 29, 2022
Biological function
In photosynthesis, the cytochrome b6f complex functions to mediate the transfer of electrons between the two photosynthetic reaction center complexes, from Photosystem II to Photosystem I, while transferring protons from the chloroplast stroma across the thylakoid membrane into the lumen.

Hereof, what happens to matter in the cytochrome complex?

Cytochrome Complex in Electron Transport
A cytochrome complex plays a key part in electron transport associated with the membranes of the thylakoids in the process of photosynthesis. It accepts electrons from Photosystem II through plastoquinone and contributes to proton transport across the membrane.

Also to know, what are photosystems 1 and 2?

Both photosystems contain many pigments that help collect light energy, as well as a special pair of chlorophyll molecules found at the core (reaction center) of the photosystem. The special pair of photosystem I is called P700, while the special pair of photosystem II is called P680.

What is the function of photosystem 1?

Photosystem I is an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from plastocyanin to ferredoxin. Ultimately, the electrons that are transferred by Photosystem I are used to produce the high energy carrier NADPH.

What is the function of Plastocyanin?

Plastocyanin is a copper-containing protein that plays a role in the electron transport process associated with photosynthesis. It serves as an electron transfer agent between the cytochrome complex which follows Photosystem II and the entry point to Photosystem I of the non-cyclic electron transfer process.

Related

What is the role of Plastoquinone?

Role in photosynthesis
The role that plastoquinone plays in photosynthesis, more specifically in the light-dependent reactions of photosynthesis, is that of a mobile electron carrier through the membrane of the thylakoid.

What are cytochromes and what is their purpose?

Cytochrome, any of a group of hemoprotein cell components that, by readily undergoing reduction and oxidation (gain and loss of electrons) with the aid of enzymes, serve a vital function in the transfer of energy within cells. Hemoproteins are proteins linked to a nonprotein, iron-bearing component.

What is cytochrome c made of?

Cytochrome c has a primary structure consisting of a chain of about 100 amino acids. Many higher-order organisms possess a chain of 104 amino acids.

What does the cytochrome complex do in photosynthesis?

Cytochrome Complex in Electron Transport
A cytochrome complex plays a key part in electron transport associated with the membranes of the thylakoids in the process of photosynthesis. It accepts electrons from Photosystem II through plastoquinone and contributes to proton transport across the membrane.

What is cyclic electron transport?

Cyclic electron transport is a light-driven flow of electrons through a photosynthetic reaction centre with the electrons returning to the reaction centre via an electron transport pathway.

What is happening with matter in PSII?

It captures photons and uses the energy to extract electrons from water molecules. These electrons are used in several ways. First, when the electrons are removed, the water molecule is broken into oxygen gas, which bubbles away, and hydrogen ions, which are used to power ATP synthesis.

What is the purpose of the Q cycle?

The Q cycle (named for quinol) describes a series of reactions that describe how the sequential oxidation and reduction of the lipophilic electron carrier, Coenzyme Q10 (CoQ10), between the ubiquinol and ubiquinone forms, can result in the net movement of protons across a lipid bilayer (in the case of the mitochondria,

Is Plastoquinone a protein?

Plastoquinone (PQ) is an isoprenoid quinone molecule involved in the electron transport chain in the light-dependent reactions of photosynthesis. The most common form of plastoquinone, known as PQ-A or PQ-9, is a 2,3-dimethyl-1,4-benzoquinone molecule with a side chain of nine isoprenyl units.

What is needed for light dependent reactions?

The light-dependent reactions use light energy to make two molecules needed for the next stage of photosynthesis: the energy storage molecule ATP and the reduced electron carrier NADPH. In plants, the light reactions take place in the thylakoid membranes of organelles called chloroplasts.

How do the cytochrome complex components involved in photosynthesis contribute to the electron transport chain?

How do the cytochrome complex components involved in photosynthesis contribute to the electron transport chain? Plastoquinone and plastocyanine perform redox reactions that allow the electron to move down the electron transport chain into Photosystem I. Electrons from PS I cause the reduction of NADP+ to NADPH.

What does the cytochrome complex produce?

A cytochrome complex plays a key part in electron transport associated with the membranes of the thylakoids in the process of photosynthesis. It accepts electrons from Photosystem II through plastoquinone and contributes to proton transport across the membrane.

How does cyanide inhibit complex 4?

Cyanide binds to Fe3+ in heme-containing proteins. This inhibits the terminal cytochrome complex IV of the electron transport chain. The blocklock of complex IV by cyanide depletes ATP culminating in cell death. Oxygen is unable to reoxidize the reduced cytochrome a3.

Which protein carrier does cyanide affect?

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.