M13 DNAs in which carbon 5 of each deoxycytidine residue in one strand is replaced with a bulky group are very good substrates for human DNA(cytosine-5)methyltransferase. Rate enhancements of up to 35 fold are obtained depending on the size of the moiety at C-5. The enzyme appears optimally suited to sense a methyl group in one strand at this position. Alkaline density gradient analyses of the distribution of methyl groups applied to 5-BrdCyd or 5-IdCyd substituted DNA reveal that these groups serve to direct the enzyme to methylate the unsubstitued strand.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - May 29 1987|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology