CLONING OF RECA AND LEXA GENES ON THE PLA SMID WITH A BROAD-HOST-RANGE

The recA gene from Escherichia coli and Propionibacterium shermanii an d lexA gene from E. coli were cloned of the plasmid pBI101 with a broa d host range. The correlation of induction of the SOS function and the dose of UV-light, MMS and 4-NQO was studied in E. coli cells carrying the plasmid pJEA3. The level of SOS response in recA cells carrying t he plasmid pBI101::recA E. coli and pBI101::rec A P. shermanii was hig her than a SOS response level in EC1000 with a normal recA gene. Howev er, no complete complementation of the SOS function was observed in re cA cells when pBI101 with recA and lexA genes was incorporated and und er the action of all mutagenic factors.