Regulation of inter- and intramolecular ligation with T4 DNA ligase in the presence of polyethylene glycol

Abstract

Polyethlene glycol (PEG) stimulates ligation with T4 DNA ligase. In 10% (w/v) PEG 6000 solutions, only intermolecular ligation is enhanced by monovalent cations, while both inter- and intramolecular ligation occur without their presence. Similar stimulation was also caused by divalent cations or polyamines in the PEG 6000 solutions. Such properties of the ligase could be applied to control the extent of inter- and intramolecular ligation. Ligation with cations or polyamines in 10% PEG 6000 solutions was effective for intermolecular ligation. Ligation without cations or polyamines in 6.0% to 10% PEG 6000 solutions was effective for intramolecular ligation. © 1986 IRL Press Limited, Oxford, England.