Identification of psiB genes of plasmids F and R6-5. Molecular basis for psiB enhanced expression in plasmid R6-5.
Nucleic Acids Res
; 16(22): 10669-79, 1988 Nov 25.
Article
em En
| MEDLINE
| ID: mdl-3205720
ABSTRACT
PsiB protein of plasmid R6-5 inhibits the induction of the SOS pathway. The F sex factor also carries a psiB gene homologous to that of R6-5. Yet, it fails to inhibit SOS induction. In order to solve this difference, we characterized the psiB genes of R6-5 and F. We found that (i) the sequences of the two psiB genes share extensive homology the predicted amino acid sequences of the two proteins differing by 5 residues, (ii) the expression of R6-5 psiB is 4 times higher than F psiB gene, (iii) in plasmid R6-5, a Tn10 transposon upstream from the psiB gene enhances psiB expression. Hence, the F sex factor may be unable to prevent SOS induction for two non-exclusive reasons (i) F PsiB protein, being slightly different from R6-5, may be less active, (ii) the level of synthesis of F PsiB protein may be insufficient to prevent SOS induction.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Fatores R
/
Fator F
/
Genes
/
Genes Bacterianos
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
1988
Tipo de documento:
Article
País de afiliação:
França