Analysis of Promoters Recognized by PvdS, an Extracytoplasmic-Function Sigma Factor Protein from Pseudomonas aeruginosa

AUTOR(ES)

Wilson, Megan J.

FONTE

American Society for Microbiology

RESUMO

The alternative sigma factor PvdS is required by Pseudomonas aeruginosa for initiation of transcription from pyoverdine (pvd) promoters. Two divergent PvdS-dependent promoters (pvdE and pvdF) were characterized by deletion analysis, and the minimal promoter region for each included a sequence element, the iron starvation (IS) box, that is present in other pvd promoters. Site-directed mutagenesis showed that the IS box elements were essential for promoter activity in vivo. Band shift assays and in vitro transcription experiments showed that a complex of PvdS and core RNA polymerase required the presence of an IS box in order to bind to and initiate transcription from pvd promoters. These results indicate that IS box elements participate in sequence-specific recognition by PvdS to enable initiation of transcription from pvd promoters and are likely to represent a −35 sequence element for this sigma factor.

Documentos Relacionados

• Functional Analysis of PvdS, an Iron Starvation Sigma Factor of Pseudomonas aeruginosa
• Cloning and characterization of pvdS, a gene required for pyoverdine synthesis in Pseudomonas aeruginosa: PvdS is probably an alternative sigma factor.
• Regulation of Motility Behavior in Myxococcus xanthus May Require an Extracytoplasmic-Function Sigma Factor
• Pyoverdine-Mediated Regulation of FpvA Synthesis in Pseudomonas aeruginosa: Involvement of a Probable Extracytoplasmic-Function Sigma Factor, FpvI
• The FecI Extracytoplasmic-Function Sigma Factor of Escherichia coli Interacts with the β′ Subunit of RNA Polymerase