Novel ionizing radiation-sensitive mutants of Deinococcus radiodurans.
Two new loci, irrB and irrI, have been identified in Deinococcus radiodurans. Inactivation of either locus results in a partial loss of resistance to ionizing radiation. The magnitude of this loss is locus specific and differentially affected by inactivation of the uvrA gene product. An irrB uvrA double mutant is more sensitive to ionizing radiation than is an irrB mutant. In contrast, the irrI uvrA double mutant and the irrI mutant are equally sensitive to ionizing radiation. The irrB and irrI mutations also reduce D. radiodurans resistance to UV radiation, this effect being most pronounced in uvrA+ backgrounds. Subclones of each gene have been isolated, and the loci have been mapped relative to each other. The irrB and irrI genes are separated by approximately 20 kb of intervening sequence that encodes the uvrA and pol genes.
Udupa
K S
KS
Department of Microbiology, Louisiana State University, Baton Rouge 70803.
O'Cain
P A
PA
Mattimore
V
V
Battista
J R
JR
D000251:Adenosine Triphosphatases / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D004307:Dose-Response Relationship, Radiation; D004352:Drug Resistance, Microbial; D029968:Escherichia coli Proteins; D005720:Gamma Rays; D015698:Genomic Library; D006095:Gram-Positive Cocci / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D008937:Mitomycins / Q000494:pharmacology; D016296:Mutagenesis; D009154:Mutation / Q000528:radiation effects*; D011836:Radiation Tolerance / Q000235:genetics*; D014170:Transformation, Genetic
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D008937:Mitomycins; D008769:Methylnitronitrosoguanidine; C068631:UvrA protein, E coli; D000251:Adenosine Triphosphatases