Identification of the recA (tif) gene product of Escherichia coli
AUTOR(ES)
Gudas, Lorraine J.
RESUMO
Treatments that inhibit DNA synthesis in recA+lexA+Escherichia coli stimulate synthesis of a 40,000 molecular weight protein species (protein X). The protein X molecules produced by wild-type and mutant E. coli strains have been compared by two-dimensional gel electrophoresis. One recA mutant (DM1415 spr recA1) produced a protein X with a more acidic isoelectric point than protein X from the wild type, demonstrating that protein X is probably the product of the recA gene. Additional mutants carrying the recA-linked tif-1 mutation yielded a protein X that was more basic than the wild-type protein, indicating that the tif-1 mutation also alters the recA protein. Protein X molecules from the above mutants and wild-type E. coli have been shown to yield similar partial products upon limited proteolysis in sodium dodecyl sulfate, indicating they are the same protein species. These and additional studies suggest that (i) the tif-1 mutation alters a site on the recA protein that is sensitive to DNA synthesis inhibition, (ii) synthesis of recA protein is self-regulated, and (iii) synthesis of recA protein is also regulated by the lexA product with lexA-suppressor mutations such as spr resulting in constitutive synthesis of recA protein.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=431684Documentos Relacionados
- Protein X is the product of the recA gene of Escherichia coli.
- Escherichia coli recA gene product inactivates phage lambda repressor.
- tif-1 mutation alters polynucleotide recognition by the recA protein of Escherichia coli.
- Organization of the recA gene of Escherichia coli.
- Evidence that the recA441 (tif-1) mutant of Escherichia coli K-12 contains a thermosensitive intragenic suppressor of RecA constitutive protease activity.
