On the Role of Restriction Enzymes of Haemophilus in Transformation and Transfection
For the past few years we have been studying the biological effects of restriction enzymes in Haemophilus (Gromkova and Goodgal, 1972; Goodgal and Gromkova, 1973a; Gromkova et al., 1973; Smith and Wilcox, 1970). It has been relatively easy to demonstrate the action of restriction enzymes on DNA in vitro; however, it is not so easy to demonstrate that these enzymes function in the same way in the cell. Although DNA restriction has been regarded as a process apart from the phenomenon of recombination, the ability of restriction enzymes to generate unique segments of DNA with specific ends indicates that these enzymes may play an essential role in the recombination process. The in vitro construction of biologically functional bacterial plasmids by the use of restriction endonucleases supports this view (Morrow and Berg, 1972; Mertz and Davis, 1972; Cohen et al., 1973). In the experiments presented below, we have attempted to compare the actions of restriction enzymes of Haemophilus in vitro and in vivo and to draw some general conclusions about the specific restriction systems involved.
KeywordsRestriction Enzyme Haemophilus Influenzae Influenzae Strain Restrictive Cell Efficient Transformation System
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