{PDOC00088}
{PS00093; N4_MTASE}
{BEGIN}
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* N-4 cytosine-specific DNA methylases signature *
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N-4 cytosine-specific DNA methylases (EC 2.1.1.113) [1,2,3] 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: 5.
-Expert(s) to contact by email:
Roberts R.J.; roberts@neb.com
Bickle T.; bickle@ubaclu.unibas.ch
-Last update: November 1997 / Text revised.
[ 1] Tao T., Walter J., Brennan K.J., Cotterman M.M., Blumenthal R.M.
"Sequence, internal homology and high-level expression of the gene for
a DNA-(cytosine N4)-methyltransferase, M.Pvu II."
Nucleic Acids Res. 17:4161-4175(1989).
PubMed=2662138
[ 2] Klimasauskas S., Timinskas A., Menkevicius S., Butkiene D., Butkus V.,
Janulaitis A.
"Sequence motifs characteristic of DNA[cytosine-N4]methyltransferases:
similarity to adenine and cytosine-C5 DNA-methylases."
Nucleic Acids Res. 17:9823-9832(1989).
PubMed=2690010
[ 3] Timinskas A., Butkus V., Janulaitis A.
"Sequence motifs characteristic for DNA [cytosine-N4] and DNA
[adenine-N6] methyltransferases. Classification of all DNA
methyltransferases."
Gene 157:3-11(1995).
PubMed=7607512
{END}