Identificació d'una nova família de caixes SOS en bacteris.

The principal aim of this work is the identification of a new family of SOS boxes in Gram-negative bacteria. Species to be analyzed will be: "Rhizobium phaseoli" and "Rhodobacter sphaeroides". These species have been selected because previous works carried out in our laboratory show that there is an interspecific regualtion between their "recA" genes, despite these bacteria being unable to control the expression of the "E. coli" "recA" gene. To achieve this aim, "in vivo" chromosomal fusions between several "din" (Damage INduction) genes from these species and the "lacZ" gene from "E. coli" will be isolated. These chromosomal fusions will be obtained by using the self-cloning minitransposon Tn5-OT182, wich carries a truncated promotorless "lacZ" gene as well as the ColE1 origin of DNA replication. "R. phaseoli" and "R. sphaeroides" clones containing "din-lacZ" fusions will be identified