23S rRNA (guanine(748)-N(1))-methyltransferase activity
23s rrna (guanine(748)-n(1))-methyltransferase activity
Catalysis of the reaction: S-adenosyl-L-methionine + guanine(748) in 23S rRNA = N(1)-methylguanine(748) in 23S rRNA + S-adenosyl-L-homocysteine.