Effects on Bacillus subtilis of a conditional lethal mutation in the essential GTP-binding protein Obg.
The obg gene is part of the spo0B sporulation operon and codes for a GTP-binding protein which is essential for growth. A temperature-sensitive mutant in the obg gene was isolated and found to be the result of two closely linked missense mutations in the amino domain of Obg. Temperature shift experiments revealed that the mutant was able to continue cell division for 2 to 3 generations at the nonpermissive temperature. Such experiments carried out during sporulation showed that Obg was necessary for the transition from vegetative growth to stage 0 or stage II of sporulation, but sporulation subsequent to these stages was unaffected at the nonpermissive temperature. Spores of the temperature-sensitive mutant germinated normally at the nonpermissive temperature but failed to outgrow. The primary consequence of the obg mutation may be an alteration in initiation of chromosome replication.
Department of Molecular and Experimental Medicine, Scripps Research Institute, La Jolla, California 92037.
J
J
Kok
K A
KA
Trach
J A
JA
Hoch
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics* / Q000254:growth & development*; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D003434:Crossing Over, Genetic; D019204:GTP-Binding Proteins / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics; D005804:Genes, Lethal / Q000235:genetics; D006358:Hot Temperature; D008969:Molecular Sequence Data; D009154:Mutation; D009876:Operon / Q000235:genetics; D011995:Recombination, Genetic; D015183:Restriction Mapping; D012808:Sigma Factor; D013171:Spores, Bacterial / Q000254:growth & development*; D014157:Transcription Factors
D001426:Bacterial Proteins; C090542:Obg GTP-binding protein, Bacteria; D012808:Sigma Factor; D014157:Transcription Factors; C092468:spoIIR protein, Bacillus subtilis; C030069:spore-specific proteins, Bacillus; D019204:GTP-Binding Proteins