IUBMB Enzyme Nomenclature


Accepted name: sucrose—1,6-α-glucan 3(6)-α-glucosyltransferase

Reaction: (1) sucrose + [(1→6)-α-D-glucosyl]n = D-fructose + [(1→6)-α-D-glucosyl]n+1
(2) sucrose + [(1→6)-α-D-glucosyl]n = D-fructose + (1→3)-α-D-glucosyl[(1→6)-α-D-glucosyl]n

Other name(s): water-soluble-glucan synthase; GTF-S; GTF-S; GTF-SI; sucrose-1,6-α-glucan 3(6)-α-glucosyltransferase; sucrose:1,6-α-D-glucan 3-α- and 6-α-glucosyltransferase; sucrose:1,6-, 1,3-α-D-glucan 3-α- and 6-α-D-glucosyltransferase; gtfB (gene name); gtfC (gene name); gtfD (gene name)

Systematic name: sucrose:(1→6)-α-D-glucan 3(6)-α-D-glucosyltransferase

Comments: The enzyme was characterized from the dental caries bacterium Streptococcus mutans. It transfers glucosyl residues from sucrose to either the 6- or the 3-positions of glucose residues in glucans, producing a highly-branched extracellular D-glucan polymers that promote attachment of the bacteria to teeth. Three types of the enzyme have been described; the insoluble polymers produced by GTF-I and GTF-SI contain 85% α(1→3) bonds and 15% α(1→6) bonds, while the soluble polymers produced by GTF-S contain only 30% of α(1→3) bonds and 70% α(1→6) bonds. cf. EC, dextransucrase [5].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 81725-87-3


1. Mukasa, H., Shimamura, A. and Tsumori, H. Purification and characterization of basic glucosyltransferase from Streptococcus mutans serotype c. Biochim. Biophys. Acta 719 (1982) 81-89. [PMID: 6216919]

2. Shimamura, A., Tsumori, H. and Mukasa, H. Purification and properties of Streptococcus mutans extracellular glucosyltransferase. Biochim. Biophys. Acta 702 (1982) 72-80. [PMID: 6461359]

3. Tsumori, H., Shimamura, A. and Mukasa, H. Purification and properties of extracellular glucosyltransferase synthesizing 1,6-, 1,3-α-D-glucan from Streptococcus mutans serotype a. J. Gen. Microbiol. 131 (1985) 3347-3353. [PMID: 2937877]

4. Fujiwara, T., Tamesada, M., Bian, Z., Kawabata, S., Kimura, S. and Hamada, S. Deletion and reintroduction of glucosyltransferase genes of Streptococcus mutans and role of their gene products in sucrose dependent cellular adherence. Microb Pathog 20 (1996) 225-233. [PMID: 8737492]

5. Monchois, V., Willemot, R.M. and Monsan, P. Glucansucrases: mechanism of action and structure-function relationships. FEMS Microbiol. Rev. 23 (1999) 131-151. [PMID: 10234842]

6. Ito, K., Ito, S., Shimamura, T., Weyand, S., Kawarasaki, Y., Misaka, T., Abe, K., Kobayashi, T., Cameron, A.D. and Iwata, S. Crystal structure of glucansucrase from the dental caries pathogen Streptococcus mutans. J. Mol. Biol. 408 (2011) 177-186. [PMID: 21354427]

[EC created 1984]

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