Erythromycin 3''-O-methyltransferase explained

Erythromycin 3-O-methyltransferase
Ec Number:	2.1.1.254

Erythromycin 3''-O-methyltransferase (EryG) is an enzyme with systematic name S-adenosyl-L-methionine:erythromycin C 3''-O-methyltransferase.^{[1] [2]} This enzyme catalyses the following chemical reaction

(1) S-adenosyl-L-methionine + erythromycin C

\rightleftharpoons S-adenosyl-L-homocysteine + erythromycin A

(2) S-adenosyl-L-methionine + erythromycin D

\rightleftharpoons S-adenosyl-L-homocysteine + erythromycin B

The enzyme methylates the 3 position of the mycarosyl moiety of erythromycin C.

Notes and References

1. Paulus TJ, Tuan JS, Luebke VE, Maine GT, DeWitt JP, Katz L . Mutation and cloning of eryG, the structural gene for erythromycin O-methyltransferase from Saccharopolyspora erythraea, and expression of eryG in Escherichia coli . Journal of Bacteriology . 172 . 5 . 2541–6 . May 1990 . 2185226 . 208895 . 10.1128/jb.172.5.2541-2546.1990 .
2. Summers RG, Donadio S, Staver MJ, Wendt-Pienkowski E, Hutchinson CR, Katz L . Sequencing and mutagenesis of genes from the erythromycin biosynthetic gene cluster of Saccharopolyspora erythraea that are involved in L-mycarose and D-desosamine production . Microbiology . 143 . 3251–62 . October 1997 . 9353926 . 10.1099/00221287-143-10-3251 . 10. free .