IUBMB Enzyme Nomenclature


Accepted name: mycothiol S-conjugate amidase

Reaction: a mycothiol S-conjugate + H2O = an N-acetyl L-cysteine-S-conjugate + 1-O-(2-amino-2-deoxy-α-D-glucopyranosyl)-1D-myo-inositol

Glossary: mycothiol = 1-O-[2-(N2-acetyl-L-cysteinamido)-2-deoxy-α-D-glucopyranosyl]-1D-myo-inositol
N-acetyl L-cysteine-S-conjugate = mercapturic acid

Other name(s): MCA

Systematic name: mycothiol S-conjugate 1D-myo-inositol 2-amino-2-deoxy-α-D-glucopyranosyl-hydrolase

Comments: The enzyme that is found in actinomycetes is involved in the detoxification of oxidizing agents and electrophilic antibiotics. The enzyme has low activity with 1-O-(2-acetamido-2-deoxy-α-D-glucopyranosyl)-1D-myo-inositol as substrate (cf. EC, N-acetyl-1-D-myo-inositol-2-amino-2-deoxy-α-D-glucopyranoside deacetylase) [2].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Newton, G.L., Av-Gay, Y. and Fahey, R.C. A novel mycothiol-dependent detoxification pathway in mycobacteria involving mycothiol S-conjugate amidase. Biochemistry 39 (2000) 10739-10746. [PMID: 10978158]

2. Steffek, M., Newton, G.L., Av-Gay, Y. and Fahey, R.C. Characterization of Mycobacterium tuberculosis mycothiol S-conjugate amidase. Biochemistry 42 (2003) 12067-12076. [PMID: 14556638]

[EC created 2013]

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