Iron–sulfur cluster biosynthesis
| Fe-S_biosyn | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 e.coli isca crystal structure to 2.3 a | |||||||||
| Identifiers | |||||||||
| Symbol | Fe-S_biosyn | ||||||||
| Pfam | PF01521 | ||||||||
| InterPro | IPR000361 | ||||||||
| PROSITE | PDOC00887 | ||||||||
| SCOP2 | 1nwb / SCOPe / SUPFAM | ||||||||
| |||||||||
In molecular biology, the iron-sulfur cluster biosynthesis protein family of includes proteins involved in biogenesis of Fe-S clusters (iron-sulfur cluster insertion protein, Fe/S biogenesis protein). Overall, iron-sulfur clusters are always on scaffolds, which are nonfunctional. The iron-sulfur cluster is then transferred to other proteins and enzymes where they are functional. The formation of iron-sulfur clusters are produced by one of four pathways:[1]
- Nitrogen fixation (NIF) system, in nitrogen-fixing bacteria[2]
- Iron-sulfur cluster (ISC) system, in bacterial and mitochondria
- Sulfur assimilation (SUF) system, in plastids and some bacteria
- Cystosolic Iron-Sulfur Assembly (CIA) for cytosolic and nuclear Fe–S proteins.
Mechanisms
Iron-sulfur cluster biosynthesis begins with the production of the persulfide of cysteine by the action of a cysteine desulfurase.
- L-cysteine + [enzyme]-cysteine L-alanine + [enzyme]-S-sulfanylcysteine
The persulfide contains the functional group R-S-S-H, which functions as a source of "inorganic sulfur" that will comprise the Fe-S proteins.
Some of the proteins associated with the biosynthesis are IscA, HesB, YadR and YfhF-like proteins. The hesB gene is expressed only under nitrogen fixation conditions, within nitrogen fixing cyanobacteria.[3] IscA, an 11 kDa member of the hesB family of proteins, binds iron and [2Fe-2S] clusters, and participates in the biosynthesis of iron-sulfur proteins. IscA is able to bind at least 2 iron ions per dimer.[4] Other members of this family include various hypothetical proteins that also contain the NifU-like domain suggesting that they too are able to bind iron and are involved in Fe-S cluster biogenesis. The HesB family are found in species as divergent as Homo sapiens (Human) and Haemophilus influenzae suggesting that these proteins are involved in basic cellular functions.[5]
References
- ^ Lill, Roland (2009). "Function and biogenesis of iron–sulphur proteins". Nature. 460 (7257): 831–838. Bibcode:2009Natur.460..831L. doi:10.1038/nature08301. PMID 19675643. S2CID 205217943.
- ^ Santos, Patricia C. Dos; Dean, Dennis R. (2017). "FeS Cluster Assembly: NIF System in Nitrogen-Fixing Bacteria". Encyclopedia of Inorganic and Bioinorganic Chemistry. pp. 1–13. doi:10.1002/9781119951438.eibc2466. ISBN 9781119951438.
- ^ Huang TC, Lin RF, Chu MK, Chen HM (March 1999). "Organization and expression of nitrogen-fixation genes in the aerobic nitrogen-fixing unicellular cyanobacterium Synechococcus sp. strain RF-1". Microbiology. 145 (3): 743–53. doi:10.1099/13500872-145-3-743. PMID 10217509.
- ^ Cupp-Vickery JR, Silberg JJ, Ta DT, Vickery LE (April 2004). "Crystal structure of IscA, an iron-sulfur cluster assembly protein from Escherichia coli". J. Mol. Biol. 338 (1): 127–37. doi:10.1016/j.jmb.2004.02.027. PMID 15050828.
- ^ Hwang DM, Dempsey A, Tan KT, Liew CC (November 1996). "A modular domain of NifU, a nitrogen fixation cluster protein, is highly conserved in evolution". J. Mol. Evol. 43 (5): 536–40. Bibcode:1996JMolE..43..536H. doi:10.1007/BF02337525. PMID 8875867. S2CID 21873104.