Summary: A recombinant plasmid, pSM2513, containing an 8·5 kb DNA insert was isolated from a genomic library of by using interspecific complementation. This plasmid conferred resistance to methyl methanesulphonate and UV irradiation upon mutants of and enhanced recombination proficiency, as measured by Hfr-mediated conjugation, in mutants of Furthermore, when mutants of harbouring pSM2513 were subjected to UV irradiation, filamentation of the cells was observed. This did not occur upon UV irradiation of the same mutants harbouring the cloning vector alone. These results imply that the S. gene on pSM2513 is functionally similar to the gene in several respects. Restriction enzyme analysis and subcloning studies revealed that the gene was located on a 2·7 kb II-I fragment of pSM2513, and its gene product of approximately 39 kDa resembled the RecA protein in molecular mass. Using transformation-mediated marker rescue, a mutant of was successfully constructed; its proficiency both in homologous recombination and in DNA repair was abolished compared with its parent.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error