dCMP + (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + H2O <=> 5-hydroxymethyl-dCMP + (6S)-5,6,7,8-tetrahydrofolate
dcmp + (6r)-5,10-methylene-5,6,7,8-tetrahydrofolate + h2o <=> 5-hydroxymethyl-dcmp + (6s)-5,6,7,8-tetrahydrofolate