title: DNA adenine methylation of GATC sequences appeared recently in the Escherichia coli lineage.
abstract: We have examined the presence of methylated adenine at GATC sequences (Dam phenotype) in the DNA of 23 eubacteria and 13 archaebacteria by using isoshizomer restriction enzymes. We have found a completely Dam+ phenotype in bacteria of nine genera related to the families Enterobacteriaceae, Parvobacteriaceae, and Vibrionaceae, and in the five cyanobacteria tested. We have found a partial Dam+ phenotype in the two archaebacteria Halobacterium saccharovorum and Methanobacterium sp. strain Ivanov. All of the other archaebacteria (three genera) and eubacteria (nine genera) tested were Dam-. Phylogenetic analysis, based on the evolutionary tree of Fox et al. (Science 209:457-463, 1980), indicates that dam methylation in the Escherichia coli lineage appeared recently in bacterial evolution and is restricted to a small range of closely related bacteria.
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives*; D001105:Archaea / Q000235:genetics*; D001419:Bacteria / Q000235:genetics*; D001483:Base Sequence; D004262:DNA Restriction Enzymes; D004269:DNA, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D006090:Gram-Negative Bacteria / Q000235:genetics*; D008745:Methylation; D010802:Phylogeny; D013045:Species Specificity
chemical_list: D004269:DNA, Bacterial; D004262:DNA Restriction Enzymes; D000225:Adenine