Biomaterial Database

Microassay for DNA methyltransferase. 1991

R L Adams, and A Rinaldi, and C Seivwright

Department of Biochemistry, University of Glasgow, UK.

A microassay for DNA methylase is described which can detect activity in as few as 50 tissue culture cells. The cells are lysed and incubated for 2 h at 37 degrees C with 3 microCi high specific activity [3H]AdoMet and 0.5 microgram poly[d(I-C).d(I-C)] in a volume of 23 microliters. Ribonuclease is present during the assay and the product DNA is isolated by phenol extraction after protease digestion.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008832	Microchemistry	The development and use of techniques and equipment to study or perform chemical reactions, with small quantities of materials, frequently less than a milligram or a milliliter.
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D015254	DNA Modification Methylases	Enzymes that are part of the restriction-modification systems. They are responsible for producing a species-characteristic methylation pattern, on either adenine or cytosine residues, in a specific short base sequence in the host cell's own DNA. This methylated sequence will occur many times in the host-cell DNA and remain intact for the lifetime of the cell. Any DNA from another species which gains entry into a living cell and lacks the characteristic methylation pattern will be recognized by the restriction endonucleases of similar specificity and destroyed by cleavage. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms.	DNA Modification Methyltransferases,Modification Methylases,Methylases, DNA Modification,Methylases, Modification,Methyltransferases, DNA Modification,Modification Methylases, DNA,Modification Methyltransferases, DNA