title: Distinct CG and CNG DNA methyltransferases in Pisum sativum.
abstract: DNA methyltransferase activity, present in low salt extracts of nuclei from young pea shoot apices, has been fractionated into two different species by assaying with model substrates. The CG methyltransferase (an unstable enzyme believed to be of 140 kDa) methylates cytosine only in oligonucleotides with CG and Cl dinucleotide targets while an enzyme of 110 kDa (the CNG methyltransferase) methylates the cytosines in 5'-CAG-3' and 5'-CTG-3' target sequences, especially when hemimethylated, but not in 5'-CCG-3' nor in 5'-CGG-3' target sequences present in oligonucleotides.
authors.affiliation: Institute of Biomedical and Life Sciences, University of Glasgow, UK.
authors.forename: S
authors.initials: S
authors.lastname: Pradhan
authors.forename: R L
authors.initials: RL
authors.lastname: Adams
mesh_terms: D001483:Base Sequence; D003432:Cross-Linking Reagents; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism; D008745:Methylation; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity
chemical_list: D003432:Cross-Linking Reagents; D018744:DNA, Plant; D004248:DNA (Cytosine-5-)-Methyltransferases