Analysis of genomic DNA from Chlamydia trachomatis for Dam and Dcm methylation.

Chlamydia trachomatis is a Gram-negative eubacterium with a dimorphic developmental cycle and obligate intracellular growth in the eucaryotic host. The Dam transmethylase of Escherichia coli methylates at the N6 position of adenine in the sequence 5'-GATC-3' and the Dcm transmethylase adds methyl groups to the C5 position of the internal cytosines in the sequences 5'-CCWGG-3'. In contrast to E. coli, C. trachomatis DNA appears to have unmethylated Dam sites and only low level Dcm methylation.