Accepted name: 2′-deamino-2′-hydroxyneamine 1-α-D-kanosaminyltransferase
Reaction: (1) UDP-α-D-kanosamine + 2′-deamino-2′-hydroxyneamine = UDP + kanamycin A
(2) UDP-α-D-kanosamine + neamine = UDP + kanamycin B
(3) UDP-α-D-kanosamine + paromamine = UDP + kanamycin C
(4) UDP-α-D-kanosamine + 2′-deamino-2′-hydroxyparomamine = UDP + kanamycin X
Glossary: neamine = (1R,2R,3S,4R,6S)-4,6-diamino-2,3-dihydroxycyclohexyl 2,6-diamino-2,6-dideoxy-α-D-glucopyranoside
paromamine = (1R,2R,3S,4R,6S)-4,6-diamino-2,3-dihydroxycyclohexyl 2-amino-2-deoxy-α-D-glucopyranoside
UDP-α-D-kanosamine = uridine 5′-[3-(3-amino-3-deoxy-α-D-glucopyranosyl) diphosphate]
kanamycin A = (1S,2R,3R,4S,6R)-4,6-diamino-3-(6-amino-6-deoxy-α-D-glucopyranosyloxy)-2-hydroxycyclohexyl 3-amino-3-deoxy-α-D-glucopyranoside
kanamycin B = (1R,2S,3S,4R,6S)-4,6-diamino-3-(3-amino-3-deoxy-α-D-glucopyranosyloxy)-2-hydroxycyclohexyl 2,6-diamino-2,6-dideoxy-α-D-glucopyranoside
kanamycin C = (1R,2S,3S,4R,6S)-4,6-diamino-3-(3-amino-3-deoxy-α-D-glucopyranosyloxy)-2-hydroxycyclohexyl 2-amino-2-deoxy-α-D-glucopyranoside
kanamycin X = (1S,2R,3R,4S,6R)-4,6-diamino-3-(α-D-glucopyranosyloxy)-2-hydroxycyclohexyl 3-amino-3-deoxy-α-D-glucopyranoside
Other name(s): kanE (gene name); kanM2 (gene name)
Systematic name: UDP-α-D-kanosamine:2′-deamino-2′-hydroxyneamine 1-α-D-kanosaminyltransferase
Comments: Involved in the biosynthetic pathway of kanamycins. The enzyme characterized from the bacterium Streptomyces kanamyceticus can also accept UDP-α-D-glucose with lower efficiency [2].
1.  Kudo, F., Sucipto, H. and Eguchi, T. Enzymatic activity of a glycosyltransferase KanM2 encoded in the kanamycin biosynthetic gene cluster. J. Antibiot. (Tokyo) 62 (2009) 707–710. [PMID: 19911031]
2.  Park, J.W., Park, S.R., Nepal, K.K., Han, A.R., Ban, Y.H., Yoo, Y.J., Kim, E.J., Kim, E.M., Kim, D., Sohng, J.K. and Yoon, Y.J. Discovery of parallel pathways of kanamycin biosynthesis allows antibiotic manipulation. Nat. Chem. Biol. 7 (2011) 843–852. [PMID: 21983602]
[EC created 2013]
Accepted name: 3-amino-5-hydroxybenzoate synthase
Reaction: 5-amino-5-deoxy-3-dehydroshikimate = 3-amino-5-hydroxybenzoate + H2O
Other name(s): AHBA synthase; rifK (gene name)
Systematic name: 5-amino-5-deoxy-3-dehydroshikimate hydro-lyase (3-amino-5-hydroxybenzoate-forming)
Comments: A pyridoxal 5′-phosphate enzyme. The enzyme from the bacterium Amycolatopsis mediterranei participates in the pathway for rifamycin B biosynthesis. The enzyme also functions as a transaminase earlier in the pathway, producing UDP-α-D-kanosamine [3].
1.  Kim, C.G., Yu, T.W., Fryhle, C.B., Handa, S. and Floss, H.G. 3-Amino-5-hydroxybenzoic acid synthase, the terminal enzyme in the formation of the precursor of mC7N units in rifamycin and related antibiotics. J. Biol. Chem. 273 (1998) 6030–6040. [PMID: 9497318]
2.  Eads, J.C., Beeby, M., Scapin, G., Yu, T.W. and Floss, H.G. Crystal structure of 3-amino-5-hydroxybenzoic acid (AHBA) synthase. Biochemistry 38 (1999) 9840–9849. [PMID: 10433690]
3.  Floss, H.G., Yu, T.W. and Arakawa, K. The biosynthesis of 3-amino-5-hydroxybenzoic acid (AHBA), the precursor of mC7N units in ansamycin and mitomycin antibiotics: a review. J. Antibiot. (Tokyo) 64 (2011) 35–44. [PMID: 21081954]
[EC created 2013]