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A motif conserved among the type I restriction-modification enzymes and antirestriction proteins: a possible basis for mechanism of action of plasmid-encoded antirestriction functions.

ABSTRACT: Antirestriction proteins Ard encoded by some self-transmissible plasmids specifically inhibit restriction by members of all three families of type I restriction-modification (R-M) systems in E.coli. Recently, we have identified the amino acid region, 'antirestriction' domain, that is conserved within different plasmid and phage T7-encoded antirestriction proteins and may be involved in interaction with the type I R-M systems. In this paper we demonstrate that this amino acid sequence shares considerable similarity with a well-known conserved sequence (the Argos repeat) found in the DNA sequence specificity (S) polypeptides of type I systems. We suggest that the presence of these similar motifs in restriction and antirestriction proteins may give a structural basis for their interaction and that the antirestriction action of Ard proteins may be a result of the competition between the 'antirestriction' domains of Ard proteins and the similar conserved domains of the S subunits that are believed to play a role in the subunit assembly of type I R-M systems.

SUBMITTER: Belogurov AA

PROVIDER: S-EPMC306760 | biostudies-other | 1995 Mar

REPOSITORIES: biostudies-other

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A motif conserved among the type I restriction-modification enzymes and antirestriction proteins: a possible basis for mechanism of action of plasmid-encoded antirestriction functions.

Belogurov A A AA Delver E P EP

Nucleic acids research 19950301 5

Antirestriction proteins Ard encoded by some self-transmissible plasmids specifically inhibit restriction by members of all three families of type I restriction-modification (R-M) systems in E.coli. Recently, we have identified the amino acid region, 'antirestriction' domain, that is conserved within different plasmid and phage T7-encoded antirestriction proteins and may be involved in interaction with the type I R-M systems. In this paper we demonstrate that this amino acid sequence shares cons ...[more]

PMID: 7708494

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Dataset Information

A motif conserved among the type I restriction-modification enzymes and antirestriction proteins: a possible basis for mechanism of action of plasmid-encoded antirestriction functions.

Publications

A motif conserved among the type I restriction-modification enzymes and antirestriction proteins: a possible basis for mechanism of action of plasmid-encoded antirestriction functions.

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