IUBMB Enzyme Nomenclature


Accepted name: aminodeoxyfutalosine nucleosidase

Reaction: 6-amino-6-deoxyfutalosine + H2O = dehypoxanthine futalosine + adenine

For diagram of reaction click here.

Glossary: 6-amino-6-deoxyfutalosine = 3-{3-[(2R,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl]propanoyl}benzoate
dehypoxanthine futalosine = 3-{3-[(2R,3S,4R)-3,4,5-trihydroxytetrahydrofuran-2-yl]propanoyl}benzoate

Other name(s): AFL nucleosidase; aminofutalosine nucleosidase; methylthioadenosine nucleosidase; MqnB (ambiguous)

Systematic name: 6-amino-6-deoxyfutalosine ribohydrolase

Comments: The enzyme, found in several bacterial species, catalyses a step in a modified futalosine pathway for menaquinone biosynthesis. While the enzyme from some organisms also has the activity of EC, adenosylhomocysteine nucleosidase, the enzyme from Chlamydia trachomatis is specific for 6-amino-6-deoxyfutalosine [7]. Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:


1. Hiratsuka, T., Furihata, K., Ishikawa, J., Yamashita, H., Itoh, N., Seto, H. and Dairi, T. An alternative menaquinone biosynthetic pathway operating in microorganisms. Science 321 (2008) 1670-1673. [PMID: 18801996]

2. Li, X., Apel, D., Gaynor, E.C. and Tanner, M.E. 5'-methylthioadenosine nucleosidase is implicated in playing a key role in a modified futalosine pathway for menaquinone biosynthesis in Campylobacter jejuni. J. Biol. Chem. 286 (2011) 19392-19398. [PMID: 21489995]

3. Arakawa, C., Kuratsu, M., Furihata, K., Hiratsuka, T., Itoh, N., Seto, H. and Dairi, T. Diversity of the early step of the futalosine pathway. Antimicrob. Agents Chemother. 55 (2011) 913-916. [PMID: 21098241]

4. Wang, S., Haapalainen, A.M., Yan, F., Du, Q., Tyler, P.C., Evans, G.B., Rinaldo-Matthis, A., Brown, R.L., Norris, G.E., Almo, S.C. and Schramm, V.L. A picomolar transition state analogue inhibitor of MTAN as a specific antibiotic for Helicobacter pylori. Biochemistry 51 (2012) 6892-6894. [PMID: 22891633]

5. Mishra, V. and Ronning, D.R. Crystal structures of the Helicobacter pylori MTAN enzyme reveal specific interactions between S-adenosylhomocysteine and the 5'-alkylthio binding subsite. Biochemistry 51 (2012) 9763-9772. [PMID: 23148563]

6. Kim, R.Q., Offen, W.A., Davies, G.J. and Stubbs, K.A. Structural enzymology of Helicobacter pylori methylthioadenosine nucleosidase in the futalosine pathway. Acta Crystallogr. D Biol. Crystallogr. 70 (2014) 177-185. [PMID: 24419390]

7. Barta, M.L., Thomas, K., Yuan, H., Lovell, S., Battaile, K.P., Schramm, V.L. and Hefty, P.S. Structural and biochemical characterization of Chlamydia trachomatis hypothetical protein CT263 supports that menaquinone synthesis occurs through the futalosine pathway. J. Biol. Chem. 289 (2014) 32214-32229. [PMID: 25253688]

[EC created 2014]

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