A beta subtype methylase that recognizes the double-stranded sequence 5'-GANTC-3' and methylates A-2 on both strands (PubMed:12654995) (By similarity). CcrM-mediated methylation has important cellular functions. Contributes to the accurate cell-cycle control of DNA replication and cellular morphology (By similarity). a 2'-deoxyadenosine in DNA + S-adenosyl-L-methionine = an N(6)-methyl-2'-deoxyadenosine in DNA + H(+) + S-adenosyl-L-homocysteine Belongs to the N(4)/N(6)-methyltransferase family.