IUBMB Enzyme Nomenclature


Accepted name: starch synthase (maltosyl-transferring)

Reaction: α-maltose 1-phosphate + [(1→4)-α-D-glucosyl]n = phosphate + [(1→4)-α-D-glucosyl]n+2

Other name(s): α1,4-glucan:maltose-1-P maltosyltransferase; GMPMT

Systematic name: α-maltose 1-phosphate:(1→4)-α-D-glucan 4-α-D-maltosyltransferase

Comments: The enzyme from from the bacterium Mycobacterium smegmatis is specific for maltose. It has no activity with α-D-glucose.

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


1. Elbein, A.D., Pastuszak, I., Tackett, A.J., Wilson, T. and Pan, Y.T. Last step in the conversion of trehalose to glycogen: a mycobacterial enzyme that transfers maltose from maltose 1-phosphate to glycogen. J. Biol. Chem. 285 (2010) 9803-9812. [PMID: 20118231]

2. Syson, K., Stevenson, C.E., Rejzek, M., Fairhurst, S.A., Nair, A., Bruton, C.J., Field, R.A., Chater, K.F., Lawson, D.M. and Bornemann, S. Structure of Streptomyces maltosyltransferase GlgE, a homologue of a genetically validated anti-tuberculosis target. J. Biol. Chem. 286 (2011) 38298-38310. [PMID: 21914799]

[EC created 2012]

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