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.