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Escherichia coli K-12 substr. MG1655 Reaction:

Superclasses: Reactions Classified By Conversion TypeSimple ReactionsChemical ReactionsComposite Reactions
Reactions Classified By SubstrateSmall-Molecule Reactions

EC Number:

Enzymes and Genes:
L-cysteine desulfuraseInferred from experiment: sufS
cysteine desulfuraseInferred from experiment: iscS

The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the direction in which it was curated.

Mass balance status: Balanced.

Enzyme Commission Primary Name: cysteine desulfurase

Enzyme Commission Synonyms: IscS, NIFS, NifS, SufS, cysteine desulfurylase

an [L-cysteine desulfurase]-L-cysteine + L-cysteine → an [L-cysteine desulfurase] L-cysteine persulfide + L-alanine,
an [L-cysteine desulfurase] L-cysteine persulfide + an unsulfurated [sulfur carrier] ↔ an [L-cysteine desulfurase]-L-cysteine + a sulfurated [sulfur carrier]

Enzyme Commission Summary:
A pyridoxal-phosphate protein. The sulfur from free L-cysteine is first transferred to a cysteine residue in the active site, and then passed on to various other acceptors. The enzyme is involved in the biosynthesis of iron-sulfur clusters, thio-nucleosides in tRNA, thiamine, biotin, lipoate and pyranopterin (molybdopterin) [Mihara02]. In Azotobacter vinelandii, this sulfur provides the inorganic sulfide required for nitrogenous metallocluster formation [Zheng93].

This is an overall reaction, which is composed of the two reactions listed above.

Citations: [Frazzon03]

Gene-Reaction Schematic

Gene-Reaction Schematic

Relationship Links: BRENDA:EC:, ENZYME:EC:, IUBMB-ExplorEnz:EC:

Created 25-Aug-2011 by Caspi R, SRI International


Frazzon03: Frazzon J, Dean DR (2003). "Formation of iron-sulfur clusters in bacteria: an emerging field in bioinorganic chemistry." Curr Opin Chem Biol 7(2);166-73. PMID: 12714048

Mihara02: Mihara H, Esaki N (2002). "Bacterial cysteine desulfurases: their function and mechanisms." Appl Microbiol Biotechnol 60(1-2);12-23. PMID: 12382038

Zheng93: Zheng L, White RH, Cash VL, Jack RF, Dean DR (1993). "Cysteine desulfurase activity indicates a role for NIFS in metallocluster biosynthesis." Proc Natl Acad Sci U S A 90(7);2754-8. PMID: 8464885

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
Page generated by SRI International Pathway Tools version 19.5 on Sat Apr 30, 2016, BIOCYC11A.