Accepted name: 8-amino-8-demethylriboflavin N,N-dimethyltransferase
Reaction: 2 S-adenosyl-L-methionine + 8-amino-8-demethylriboflavin = 2 S-adenosyl-L-homocysteine + roseoflavin (overall reaction)
(1a) S-adenosyl-L-methionine + 8-amino-8-demethylriboflavin = S-adenosyl-L-homocysteine + 8-demethyl-8-(methylamino)riboflavin
(1b) S-adenosyl-L-methionine + 8-demethyl-8-(methylamino)riboflavin = S-adenosyl-L-homocysteine + roseoflavin
Glossary: roseoflavin = 8-demethyl-8-(dimethylamino)riboflavin
Other name(s): rosA (gene name)
Systematic name: S-adenosyl-L-methionine:8-amino-8-demethylriboflavin N,N-dimethyltransferase
Comments: The enzyme, characterized from the soil bacterium Streptomyces davawensis, catalyses the last two steps in the biosynthesis of the antibiotic roseoflavin.
1.  Jankowitsch, F., Kuhm, C., Kellner, R., Kalinowski, J., Pelzer, S., Macheroux, P. and Mack, M. A novel N,N-8-amino-8-demethyl-D-riboflavin dimethyltransferase (RosA) catalyzing the two terminal steps of roseoflavin biosynthesis in Streptomyces davawensis. J. Biol. Chem. 286 (2011) 38275–38285. [PMID: 21911488]
2.  Tongsook, C., Uhl, M.K., Jankowitsch, F., Mack, M., Gruber, K. and Macheroux, P. Structural and kinetic studies on RosA, the enzyme catalysing the methylation of 8-demethyl-8-amino-D-riboflavin to the antibiotic roseoflavin. FEBS J. 283 (2016) 1531–1549. [PMID: 26913589]
[EC created 2017]