[Determination of restrictase activity in toluene lysates of bacterial cells]

A rapid method for determination of restrictase Bam H1 activity in bacterial cells has been devised. It is based on cell treatment with toluene followed by incubation of toluene lysates with DNA substrate. The method is unsophisticated, well reproducible and requires insignificant amount of biomass necessary for testing the restrictase activity, which makes it compare very favourably with the known methods. The treatment of microbial cells with toluene can serve the first stage in purification of restriction endonucleases.