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Iron–sulfur clusters are molecular ensembles of iron and sulfide. They are most often discussed in the context of the biological role for iron–sulfur proteins , which are pervasive. [ 2 ] Many Fe–S clusters are known in the area of organometallic chemistry and as precursors to synthetic analogues of the biological clusters.
Iron–sulfur proteins are proteins characterized by the presence of iron–sulfur clusters containing sulfide-linked di-, tri-, and tetrairon centers in variable oxidation states. Iron–sulfur clusters are found in a variety of metalloproteins , such as the ferredoxins , as well as NADH dehydrogenase , hydrogenases , coenzyme Q – cytochrome ...
The assembly of iron–sulfur clusters cluster begins with the production of the equivalent of a sulfur (sulfur atoms per se are not found in nature). The required sulfur atom is obtained from free cysteine by the action of so-called cysteine desulfurases. One prominent desulfurase is called IscS, a pyridoxal phosphate-dependent enzyme.
The high reduction potential of the N2 cluster and the relative proximity of the other clusters in the chain enable efficient electron transfer over long distance in the protein (with transfer rates from NADH to N2 iron-sulfur cluster of about 100 μs). [12] [13] The equilibrium dynamics of Complex I are primarily driven by the quinone redox cycle.
They participate in electron-transfer sequences. The core structure for the [Fe 4 S 4] cluster is a cube with alternating Fe and S vertices. These clusters exist in two oxidation states with a small structural change. Two families of [Fe 4 S 4] clusters are known: the ferredoxin (Fd) family and the high-potential iron–suflur protein (HiPIP ...
The iron–sulfur world hypothesis is a set of proposals for the origin of life and the early evolution of life advanced in a series of articles between 1988 and 1992 by Günter Wächtershäuser, a Munich patent lawyer with a degree in chemistry, who had been encouraged and supported by philosopher Karl R. Popper to publish his ideas.
Outer sphere ET is the basis of the biological function of the iron-sulfur proteins. The Fe centers are typically further coordinated by cysteinyl ligands. The [Fe 4 S 4] electron-transfer proteins ([Fe 4 S 4] ferredoxins) may be further subdivided into low-potential (bacterial-type) and high-potential (HiPIP) ferredoxins. Low- and high ...
In 1979, Trumpower's team isolated the "oxidation factor" from bovine mitochondria and showed it was a reconstitutively-active form of the Rieske iron-sulfur protein. [2] It is a unique [2Fe-2S] cluster in that one of the two Fe atoms is coordinated by two histidine residues rather than two cysteine residues.