Ferredoxin: Difference between revisions

Latest revision as of 03:31, 13 February 2025

Overview[edit]

Ferredoxin is a type of iron-sulfur protein that mediates electron transfer in a range of metabolic reactions. These proteins are characterized by their iron-sulfur clusters, which are responsible for their electron transfer capabilities. Ferredoxins are found in plants, algae, and some bacteria, playing a crucial role in photosynthesis, nitrogen fixation, and other biochemical pathways.

Structure[edit]

Ferredoxins typically contain iron and sulfur atoms arranged in clusters. The most common types of clusters are the [2Fe-2S] and [4Fe-4S] clusters. These clusters are coordinated by cysteine residues in the protein, which help stabilize the structure and facilitate electron transfer.

Function[edit]

Ferredoxins function primarily as electron carriers. In photosynthesis, ferredoxin receives electrons from photosystem I and transfers them to NADP+ reductase, which then reduces NADP+ to NADPH. This process is essential for the Calvin cycle in chloroplasts.

In nitrogen fixation, ferredoxins transfer electrons to nitrogenase, the enzyme responsible for converting atmospheric nitrogen (N_) into ammonia (NH_), a form that can be assimilated by plants.

Types of Ferredoxins[edit]

There are several types of ferredoxins, classified based on their iron-sulfur cluster composition and their source organism:

Plant-type ferredoxins: These contain [2Fe-2S] clusters and are primarily involved in photosynthesis.
Bacterial-type ferredoxins: These can contain [4Fe-4S] clusters and are involved in various metabolic pathways, including nitrogen fixation and hydrogen production.

Biological Importance[edit]

Ferredoxins are vital for the energy conversion processes in cells. By facilitating electron transfer, they help maintain the flow of energy and reducing power necessary for cellular metabolism. Their role in photosynthesis and nitrogen fixation highlights their importance in both energy production and nutrient assimilation.

Related Pages[edit]

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-{{png-image}}
+{{DISPLAYTITLE:Ferredoxin}}
-'''Ferredoxin''' is a [[protein]] that plays a critical role in the [[electron transport chain]], which is a key component of [[photosynthesis]] and [[cellular respiration]] in [[organisms]]. Ferredoxins are [[iron-sulfur proteins]] that mediate electron transfer in a range of metabolic reactions. They are found in the [[chloroplasts]] of [[plants]], the [[mitochondria]] of animals, and in the cells of [[bacteria]] and [[archaea]].
-The structure of ferredoxin consists of a [[polypeptide]] chain that binds iron and sulfur atoms to form iron-sulfur clusters. These clusters are responsible for the electron transfer activity of the protein. The most common type of cluster found in ferredoxin is the [2Fe-2S] cluster, although some ferredoxins contain [4Fe-4S] clusters.
+== Overview ==
+[[File:FdRedox.png|thumb|right|Diagram of ferredoxin redox reactions]]
+'''Ferredoxin''' is a type of [[iron-sulfur protein]] that mediates electron transfer in a range of metabolic reactions. These proteins are characterized by their iron-sulfur clusters, which are responsible for their electron transfer capabilities. Ferredoxins are found in plants, algae, and some bacteria, playing a crucial role in [[photosynthesis]], [[nitrogen fixation]], and other biochemical pathways.
-Ferredoxins function by accepting or donating electrons, typically from a [[reductase]] enzyme to an [[oxidase]] enzyme, in various biochemical pathways. In photosynthesis, ferredoxin is reduced (gains electrons) by the [[photosystem I]] and then donates these electrons to the enzyme [[NADP+ reductase]], which uses them to reduce [[NADP+]] to [[NADPH]], a key molecule in the synthesis of [[carbohydrates]].
+== Structure ==
+Ferredoxins typically contain iron and sulfur atoms arranged in clusters. The most common types of clusters are the [2Fe-2S] and [4Fe-4S] clusters. These clusters are coordinated by cysteine residues in the protein, which help stabilize the structure and facilitate electron transfer.
-In [[nitrogen fixation]], ferredoxin provides electrons for the reduction of [[nitrogen gas]] (N2) to [[ammonia]] (NH3) by the enzyme [[nitrogenase]]. This process is crucial for incorporating atmospheric nitrogen into organic compounds and supports the growth of plants and the productivity of ecosystems.
+== Function ==
+Ferredoxins function primarily as electron carriers. In [[photosynthesis]], ferredoxin receives electrons from [[photosystem I]] and transfers them to [[NADP+]] reductase, which then reduces NADP+ to NADPH. This process is essential for the [[Calvin cycle]] in [[chloroplasts]].
-Ferredoxins also play a role in the [[sulfur metabolism]] of some organisms, where they participate in the reduction of sulfite to sulfide in the process of synthesizing [[cysteine]], an important [[amino acid]].
+In [[nitrogen fixation]], ferredoxins transfer electrons to [[nitrogenase]], the enzyme responsible for converting atmospheric nitrogen (N_) into ammonia (NH_), a form that can be assimilated by plants.
-Given their widespread presence and essential functions, ferredoxins are considered fundamental components of life, especially in the context of energy conversion and the biosynthesis of critical biomolecules.
+== Types of Ferredoxins ==
+There are several types of ferredoxins, classified based on their iron-sulfur cluster composition and their source organism:
+* '''Plant-type ferredoxins''': These contain [2Fe-2S] clusters and are primarily involved in photosynthesis.
+* '''Bacterial-type ferredoxins''': These can contain [4Fe-4S] clusters and are involved in various metabolic pathways, including nitrogen fixation and [[hydrogen production]].
+== Biological Importance ==
+Ferredoxins are vital for the energy conversion processes in cells. By facilitating electron transfer, they help maintain the flow of energy and reducing power necessary for cellular metabolism. Their role in photosynthesis and nitrogen fixation highlights their importance in both energy production and nutrient assimilation.
+== Related Pages ==
+* [[Iron-sulfur protein]]
+* [[Photosynthesis]]
+* [[Nitrogen fixation]]
+* [[Electron transport chain]]
 [[Category:Proteins]]
-[[Category:Electron carriers]]
 [[Category:Photosynthesis]]
-[[Category:Cellular respiration]]
+[[Category:Metabolism]]
-{{biochemistry-stub}}