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- **************************************************
- * N-4 cytosine-specific DNA methylases signature *
- **************************************************
-
- N-4 cytosine-specific DNA methylases (EC 2.1.1.113) [1,2] are enzymes that
- specifically methylate the amino group at the C-4 position of cytosines in
- DNA. Such enzymes are found as components of type II restriction-modification
- systems in prokaryotes. Such enzymes recognize a specific sequence in DNA and
- methylate a cytosine in that sequence. By this action they protect DNA from
- cleavage by type II restriction enzymes that recognize the same sequence.
-
- Type II N-4 Mtases seem to be structurally and enzymatically related to N-6
- adenine-specific DNA methylases. Like the N-6 Mtases they contain a conserved
- Pro-Pro-Tyr/Phe region, but the N- and C-terminal contexts of this region are
- sufficiently different to derive a consensus pattern specific to this type of
- enzymes.
-
- -Consensus pattern: [LIVMF]-T-S-P-P-[FY]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: O'Nyong-Nyong virus nonstructural
- polyprotein and fission yeast rad16.
-
- -Expert(s) to contact by email: Roberts R.J.
- roberts@neb.com
- Bickle T.
- bickle@urz.unibas.ch
-
- -Last update: June 1994 / Pattern and text revised.
-
- [ 1] Tao T., Walter J., Brennan K.J., Cotterman M.M., Blumenthal R.M.
- Nucleic Acids Res. 17:4161-4175(1989).
- [ 2] Klimasauskas S., Timinskas A., Menkevicius S., Butkiene D., Butkus V.,
- Janulaitis A.
- Nucleic Acids Res. 17:9823-9832(1989).
-