The ATP-dependent Restriction Endonucleases

Abstract

The phenomenon of restriction and modification in bacteria was first described close to 30 years ago by Luria and Human (1952) for T-even bacteriophages and by Bertani and Weigle (1953) for phages P2 and λ. The system active against T-even phages (reviewed by Revel and Luria 1970) turned out to be unique to these phages and will not be discussed here. The effect noted by Bertani and Weigle is far more general and can be demonstrated with many different bacteriophages and hosts. The observation was that a phage stock could have different plating efficiencies when tested on closely related bacterial strains. If, however, a stock of phage was prepared on a strain that initially had grown it poorly, that stock would now grow efficiently on that strain. This acquired ability showed Lamarckian characteristics, since it was an adaptive response of the virus to the host and was lost when the virus was passaged through other hosts.

Some 10 years later, the first of a series of papers from Arber’s group appeared that provided a molecular explanation for this effect (Arber and Dussoix 1962; Dussoix and Arber 1962). Physiological and genetic experiments showed that restriction and modification operated on the DNA of the infecting phage. Restriction was due to the action of a nuclease that recognized specific sequences in the incoming DNA, and modification was due to the action of another enzyme, early suspected to be a DNA methylase (Arber 1965), that modified these same specific sequences in such a way...