label: a cytidine in 28S rRNA + S-adenosyl-L-methionine <=> a 5-methylcytidine in 28S rRNA + S-adenosyl-L-homocysteine + H(+)
label_lc: a cytidine in 28s rrna + s-adenosyl-l-methionine <=> a 5-methylcytidine in 28s rrna + s-adenosyl-l-homocysteine + h(+)