title: Methylated bases in mycoplasmal DNA.
abstract: The DNAs of four Mycoplasma and one Acholeplasma species were found to contain methylated bases. All of the five species contained 6-methyladenine (m6Ade), the methylated base characteristic of prokaryotic DNA. The extent of methylation of adenine residues in the mycoplasmal DNA ranged from 0.2% in Mycoplasma capricolum to about 2% in Mycoplasma arginini and Mycoplasma hyorhinis with intermediate methylation values for Mycoplasma orale and Acholeplasma laidlawii DNAs. About 5.8% of the cytosine residues in M. hyorhinis DNA were methylated also. Analysis of cell culture DNA for the presence of m6Ade as a means for detection of contamination by mycoplasmas, and the phylogenetic implications of the finding of methylated bases in mycoplasmal DNAs are discussed.
mesh_terms: D044503:5-Methylcytosine; D000128:Acholeplasma laidlawii / Q000378:metabolism*; D000225:Adenine / Q000031:analogs & derivatives / Q000378:metabolism; D001482:Base Composition; D003596:Cytosine / Q000031:analogs & derivatives / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism*; D008745:Methylation; D009174:Mycoplasma / Q000378:metabolism*
chemical_list: D044503:5-Methylcytosine; D000225:Adenine; D003596:Cytosine; D004269:DNA, Bacterial; C000730567:6-methyladenine