IUBMB Enzyme Nomenclature


Accepted name: N-acetyl-1D-myo-inositol-2-amino-2-deoxy-α-D-glucopyranoside deacetylase

Reaction: 1-O-(2-acetamido-2-deoxy-α-D-glucopyranosyl)-1D-myo-inositol + H2O = 1-O-(2-amino-2-deoxy-α-D-glucopyranosyl)-1D-myo-inositol + acetate

For diagram of reaction click here

Glossary: mycothiol = 1-O-[2-(N2-acetyl-L-cysteinamido)-2-deoxy-α-D-glucopyranosyl]-1D-myo-inositol

Other name(s): MshB

Systematic name: 1-(2-acetamido-2-deoxy-α-D-glucopyranosyl)-1D-myo-inositol acetylhydrolase

Comments: This enzyme is considered the key enzyme and rate limiting step in the mycothiol biosynthesis pathway [1]. In addition to acetylase activity, the enzyme possesses weak activity of EC, mycothiol S-conjugate amidase, and shares sequence similarity with that enzyme [2]. The enzyme requires a divalent transition metal ion for activity, believed to be Zn2+ [3].

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


1. Rawat, M., Kovacevic, S., Billman-Jacobe, H. and Av-Gay, Y. Inactivation of mshB, a key gene in the mycothiol biosynthesis pathway in Mycobacterium smegmatis. Microbiology 149 (2003) 1341-1349. [PMID: 12724395]

2. Newton, G.L., Av-Gay, Y. and Fahey, R.C. N-Acetyl-1-D-myo-inosityl-2-amino-2-deoxy-α-D-glucopyranoside deacetylase (MshB) is a key enzyme in mycothiol biosynthesis. J. Bacteriol. 182 (2000) 6958-6963. [PMID: 11092856]

3. Maynes, J.T., Garen, C., Cherney, M.M., Newton, G., Arad, D., Av-Gay, Y., Fahey, R.C. and James, M.N. The crystal structure of 1-D-myo-inosityl 2-acetamido-2-deoxy-α-D-glucopyranoside deacetylase (MshB) from Mycobacterium tuberculosis reveals a zinc hydrolase with a lactate dehydrogenase fold. J. Biol. Chem. 278 (2003) 47166-47170. [PMID: 12958317]

[EC created 2010]

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