Catalysis of the reaction: methyl-dCpdG DNA + H2O = dCpdG DNA + methanol. This reaction is the hydrolytic removal of the methyl group on the 5 position of cytosine in DNA.
Synonyms:
exact_synonym:
DNA methyltransferase activity acting on cytosine C-5
broad_synonym:
DNA demethylase activity; hydrolytic DNA demethylase activity