1.
Org Lett
; 24(49): 8975-8979, 2022 12 16.
Article
in English
| MEDLINE
| ID: mdl-36458844
ABSTRACT
The radical S-adenosyl-l-methionine (SAM) methylase Orf29 catalyzes the C-methylation of SAM in the biosynthesis of 1-amino-2-methylcyclopropanecarboxylic acid. Here, we determined that the methylation product is (4â³R)-4â³-methyl-SAM. Furthermore, we found that the 5'-deoxyadenosyl radical generated by Orf29 abstracts the pro-R hydrogen atom from the C-4â³ position of SAM to generate the radical intermediate, which reacts with methylcobalamin to give (4â³R)-4â³-methyl-SAM. Consequently, the Orf29-catalyzed C-methylation was confirmed to proceed with retention of configuration.