1. D protein of miniF plasmid acts as a repressor of transcription and as a site-specific resolvase
- Author
-
Lane, D., Defeyter, R., Martin Kennedy, Phua, S. H., and Semon, D.
- Subjects
Base Sequence ,Transcription, Genetic ,Escherichia coli Proteins ,Transposases ,DNA Restriction Enzymes ,Nucleotidyltransferases ,Repressor Proteins ,Phenotype ,Bacterial Proteins ,Species Specificity ,Genes, Bacterial ,Escherichia coli ,Promoter Regions, Genetic ,Plasmids ,Transcription Factors - Abstract
Two activities of the D protein of the miniF plasmid have been found. Divergent promoters in ori-1 ("primary" replicative origin) of miniF are both repressed in cells which produce D protein. The mobilization of plasmids containing the ori-1 region by the F conjugation system is also repressed by D protein. In the former case D appears to act as a transcriptional repressor, whereas in the latter case D protein acts by resolving cointegrates of F and the mobilized plasmid. D protein resolves dimers whose monomer units contain the rfsF sequence needed for recA-independent, site-specific recombination of F. The nucleotide sequence of the D gene was determined. The D gene region contains two oppositely-oriented open reading frames which have the same reading phase and substantially overlap. Transposon insertion mutants were used to show that the gene for D protein occupies the top-strand (left-to-right) open reading frame.
- Published
- 1986