Control of A Multisubunit DNA Motor by a Thermoresponsive Polymer Switch

The conjugation of thermoresponsive polymers to multisubunit, multifunctional hybrid type 1 DNA restriction−modification (R−M) enzymes enables temperature-controlled “switching” of DNA methylation by the conjugate. Polymers attached to the enzyme at a subunit distal to the methylation subunit allow retention of DNA recognition and ATPase activity while controlling methylation of plasmid DNA. This regulation of enzyme activity arises from the coil−globule phase transitions of the polymer as shown in light scattering and gel retardation assays.