A cautionary note on the use of certain restriction endonucleases with methylated substrates.
Methylation of adenine and cytosine residues in DNA isolated from common strains of Escherichia coli K-12 can render that DNA resistant to cleavage by certain restriction endonucleases at those sites at which the recognition sequence for such an endonuclease overlaps (but does not include) a sequence recognized by methylases specified by the dam or dcm gene.
D000225:Adenine; D003596:Cytosine; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism; D004262:DNA Restriction Enzymes / Q000378:metabolism*; D004269:DNA, Bacterial / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics*; D005796:Genes; D008745:Methylation; D013379:Substrate Specificity
D004269:DNA, Bacterial; D003596:Cytosine; D004248:DNA (Cytosine-5-)-Methyltransferases; D004262:DNA Restriction Enzymes; D000225:Adenine