title: Characterization of DNA methyltransferase from bovine thymus cells.
abstract: A DNA methyltransferase was partially purified from bovine thymus heavy cells. The enzyme has Mr 130 000, and introduces methyl groups from S-adenosylmethionine into the 5 position of cytosines in DNA. Sequence specificity analysis revealed that about 60% of the total methylation occurred in the 5'd(C-G)3' doublet. Single-stranded and hemi-methylated DNAs were methylated at an elevated rate by the enzyme. The kinetic analysis showed that the reaction obeys a random sequential mechanism. These results suggest that the enzyme serves primarily as a maintenance DNA methyltransferase.
mesh_terms: D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000302:isolation & purification*; D007700:Kinetics; D008780:Methyltransferases / Q000302:isolation & purification*; D013950:Thymus Gland / Q000201:enzymology*
chemical_list: D008780:Methyltransferases; D004248:DNA (Cytosine-5-)-Methyltransferases