SOS-like induction in Bacillus subtilis: induction of the RecA protein analog and a damage-inducible operon by DNA damage in Rec+ and DNA repair-deficient strains

Journal Article · Fri Apr 01 04:00:00 EST 1988 · J. Bacteriol.; (United States)

OSTI ID:7252625

Lovett, Jr, C M; Love, P E; Yasbin, R E; Roberts, J W

We quantitated the induction of the Bacillus subtilis Rec protein (the analog of Escherichia coli RecA protein) and the B. subtilis din-22 operon (representative of a set of DNA damage-inducible operons in B. subtilis) following DNA damage in Rec+ and DNA repair-deficient strains. After exposure to mitomycin C or UV irradiation, each of four distinct rec (recA1, recB2, recE4, and recM13) mutations reduced to the same extent the rates of both Rec protein induction (determined by densitometric scanning of immunoblot transfers) and din-22 operon induction (determined by assaying beta-galactosidase activity in din-22::Tn917-lacZ fusion strains). The induction deficiencies in recA1 and recE4 strains were partially complemented by the E. coli RecA protein, which was expressed on a plasmid in B. subtilis; the E. coli RecA protein had no effect on either induction event in Rec+, recB2, or recM13 strains. These results suggest that (i) the expression of both the B. subtilis Rec protein and the din-22 operon share a common regulatory component, (ii) the recA1 and recE4 mutations affect the regulation and/or activity of the B. subtilis Rec protein, and (iii) an SOS regulatory system like the E. coli system is highly conserved in B. subtilis. We also showed that the basal level of B. subtilis Rec protein is about 4,500 molecules per cell and that maximum induction by DNA damage causes an approximately fivefold increase in the rate of Rec protein accumulation.

• Research Organization: Williams College, Williamstown, MA (USA)
• OSTI ID: 7252625
• Journal Information: J. Bacteriol.; (United States), Journal Name: J. Bacteriol.; (United States) Vol. 170:4; ISSN JOBAA
• Country of Publication: United States
• Language: English

Related Subjects

560130* -- Radiation Effects on Microorganisms
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACILLUS
BACILLUS SUBTILIS
BACTERIA
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CONSTITUENTS
DNA REPAIR
ELECTROMAGNETIC RADIATION
ENZYME INDUCTION
GENE RECOMBINATION
GENE REGULATION
GENETIC EFFECTS
GENETIC RADIATION EFFECTS
MICROORGANISMS
MUTATIONS
PLASMIDS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RECOVERY
REPAIR
ULTRAVIOLET RADIATION