Marinus M G, Morris N R
Mutat Res. 1975 Apr;28(1):15-26. doi: 10.1016/0027-5107(75)90309-7.
The dam-3 mutation results in a five-fold reduction in the number of 6-methyl-adenine (6-meA) residues in the DNA of E. coli K12 or phage lambda. The DNA of phage fd appears to be devoid of 6-meA when propagated on dam-3 bacteria. The phenotypic differences between dam-3 and dam+ bacteria include: (i) increased free phage in lysogenic dam-3 cultures, (2) increased sensitivity to methyl methanesulfonate (MMS), (3) inviability of dam-3 lex-I strains, (4) lower molecular weight of DNA in dam-3 bacteria in the absence of DNA ligase and (5) increased rate of DNA degradation in dam-3 recA strains.
dam-3突变导致大肠杆菌K12或噬菌体λ DNA中6-甲基腺嘌呤（6-meA）残基数量减少五倍。当在dam-3细菌上繁殖时，噬菌体fd的DNA似乎不含6-meA。dam-3和dam+细菌之间的表型差异包括：（i）溶原性dam-3培养物中游离噬菌体增加，（2）对甲基磺酸甲酯（MMS）的敏感性增加，（3）dam-3 lex-I菌株无法存活，（4）在没有DNA连接酶的情况下，dam-3细菌中DNA的分子量较低，以及（5）dam-3 recA菌株中DNA降解速率增加。
