preferred_name: a cytidine in mRNA + H2O + H(+) => a uridine in mRNA + NH4(+)
preferred_name_lc: a cytidine in mrna + h2o + h(+) => a uridine in mrna + nh4(+)
label: a cytidine in mRNA + H2O + H(+) => a uridine in mRNA + NH4(+)
label_lc: a cytidine in mrna + h2o + h(+) => a uridine in mrna + nh4(+)