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MetaCyc Reaction:

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

EC Number:

Enzymes and Genes:

Arabidopsis thaliana col: O-acetylserine (thiol) lyaseInferred from experiment: oasA1
O-acetylserine (thiol) lyaseInferred from experiment: oasB
O-acetylserine (thiol) lyaseInferred from experiment: oasC
Astragalus bisulcatus: cysteine synthaseInferred from experiment
Escherichia coli K-12 substr. MG1655: O-acetylserine sulfhydrylase AInferred from experiment: cysK
cysteine synthase BInferred from experiment: cysM
Streptomyces lavendulae lavendulae: O-ureido-L-serine synthaseInferred from experiment: dcsD

In Pathway: L-cysteine biosynthesis I

Supersedes EC number:

The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the Enzyme Commission system.

Most BioCyc compounds have been protonated to a reference pH value of 7.3. Please see the PGDB Concepts Guide for more information.

Mass balance status: Balanced.

Enzyme Commission Primary Name: cysteine synthase

Enzyme Commission Synonyms: O-acetyl-L-serine sulfhydrylase, O-acetyl-L-serine sulfohydrolase, O-acetylserine (thiol)-lyase, O-acetylserine (thiol)-lyase A, O-acetylserine sulfhydrylase, O3-acetyl-L-serine acetate-lyase (adding hydrogen-sulfide), acetylserine sulfhydrylase, cysteine synthetase, S-sulfocysteine synthase, 3-O-acetyl-L-serine:hydrogen-sulfide 2-amino-2-carboxyethyltransferase, O3-acetyl-L-serine:hydrogen-sulfide 2-amino-2-carboxyethyltransferase

Standard Gibbs Free Energy (ΔrG in kcal/mol): -11.374123Inferred by computational analysis [Latendresse13]

Enzyme Commission Summary:
A pyridoxal-phosphate protein. Some alkyl thiols, cyanide, pyrazole and some other heterocyclic compounds can act as acceptors. Not identical with EC, β-pyrazolylalanine synthase, EC, L-mimosine synthase and EC, uracilylalanine synthase.

Citations: [Becker69, Hara90, Tai01, Bettati00 , Ikegami87, Murakoshi86]

Gene-Reaction Schematic

Gene-Reaction Schematic

Unification Links: KEGG:R00897, Rhea:14829

Relationship Links: BRENDA:EC:, ENZYME:EC:, IUBMB-ExplorEnz:EC:, UniProt:RELATED-TO:O05393, UniProt:RELATED-TO:O32978, UniProt:RELATED-TO:O34476, UniProt:RELATED-TO:O45679, UniProt:RELATED-TO:O67507, UniProt:RELATED-TO:O81154, UniProt:RELATED-TO:O81155, UniProt:RELATED-TO:O81523, UniProt:RELATED-TO:P0A1E3, UniProt:RELATED-TO:P0A534, UniProt:RELATED-TO:P0ABK5, UniProt:RELATED-TO:P16703, UniProt:RELATED-TO:P29848, UniProt:RELATED-TO:P31300, UniProt:RELATED-TO:P32260, UniProt:RELATED-TO:P37887, UniProt:RELATED-TO:P38076, UniProt:RELATED-TO:P45040, UniProt:RELATED-TO:P47998, UniProt:RELATED-TO:P47999, UniProt:RELATED-TO:P53206, UniProt:RELATED-TO:P56067, UniProt:RELATED-TO:P63873, UniProt:RELATED-TO:P71128, UniProt:RELATED-TO:P80608, UniProt:RELATED-TO:P87131, UniProt:RELATED-TO:Q7M1J2, UniProt:RELATED-TO:Q93244, UniProt:RELATED-TO:Q9CHF0, UniProt:RELATED-TO:Q9CI26, UniProt:RELATED-TO:Q9JQL6, UniProt:RELATED-TO:Q9RAS8, UniProt:RELATED-TO:Q9RW80, UniProt:RELATED-TO:Q9S2H1, UniProt:RELATED-TO:Q9S6Z7, UniProt:RELATED-TO:Q9S757, UniProt:RELATED-TO:Q9SMY4, UniProt:RELATED-TO:Q9UWP0, UniProt:RELATED-TO:Q9V1Q3, UniProt:RELATED-TO:Q9WZD3, UniProt:RELATED-TO:Q9XDU7, UniProt:RELATED-TO:Q9ZMW6, UniProt:RELATED-TO:Q00834, UniProt:RELATED-TO:Q43153, UniProt:RELATED-TO:Q43317, UniProt:RELATED-TO:Q43725, UniProt:RELATED-TO:Q43726, UniProt:RELATED-TO:Q59447, UniProt:RELATED-TO:Q59529

Revised 10-Oct-2011 by Caspi R, SRI International


Becker69: Becker MA, Kredich NM, Tomkins GM (1969). "The purification and characterization of O-acetylserine sulfhydrylase-A from Salmonella typhimurium." J Biol Chem 244(9);2418-27. PMID: 4891157

Bettati00: Bettati S, Benci S, Campanini B, Raboni S, Chirico G, Beretta S, Schnackerz KD, Hazlett TL, Gratton E, Mozzarelli A (2000). "Role of pyridoxal 5'-phosphate in the structural stabilization of O-acetylserine sulfhydrylase." J Biol Chem 275(51);40244-51. PMID: 10995767

Hara90: Hara S, Payne MA, Schnackerz KD, Cook PF (1990). "A rapid purification procedure and computer-assisted sulfide ion selective electrode assay for O-acetylserine sulfhydrylase from Salmonella typhimurium." Protein Expr Purif 1(1);70-6. PMID: 2152186

Ikegami87: Ikegami F, Kaneko M, Lambein F, Kuo Y-H, Murakoshi I (1987). "Difference between uracilylalanine synthases and cysteine synthases in Pisum sativum." Phytochemistry 26 2699-2704.

Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Murakoshi86: Murakoshi I, Kaneko M, Koide C, Ikegami F (1986). "Enzymatic-synthesis of the neuroexcitatory amino-acid quisqualic by cysteine synthase." Phytochemistry 25 2759-2763.

Tai01: Tai CH, Burkhard P, Gani D, Jenn T, Johnson C, Cook PF (2001). "Characterization of the allosteric anion-binding site of O-acetylserine sulfhydrylase." Biochemistry 40(25);7446-52. PMID: 11412097

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by Pathway Tools version 19.5 (software by SRI International) on Wed May 4, 2016, biocyc13.