DNA-Binding proteins possibly involved in regulation of the post-logarithmic-phase expression of lipoprotein P35 in Borrelia burgdorferi.
Previously, we have shown that the transcription of p35, a lipoprotein gene of Borrelia burgdorferi, is upregulated or initiated during the post-logarithmic bacterial growth phase in vitro. To identify potential regulatory factors, we examined the formation of DNA-protein complexes by electromobility shift assay, using a 157-bp DNA fragment that spans the p35 promoter region and cell-free extracts of spirochetes harvested from both logarithmic and stationary growth phases. The binding properties of the extracts with the promoter region of the flaB gene, a constitutively expressed, growth-phase-independent gene, were also compared. The results from these experiments demonstrate that B. burgdorferi stationary-phase cell-free extracts have a growth-phase-dependent DNA binding protein that interacts specifically with the p35 promoter region. We show, in addition, that a segment from the 157-bp p35 promoter region which contains both a T-rich stretch and an inverted repeat is able to compete off the stationary-phase-specific complex when the segment is present in molar excess.
Indest
K J
KJ
Department of Parasitology, Tulane Regional Primate Research Center, Tulane University Medical Center, Covington, Louisiana, USA.
Philipp
M T
MT
D000942:Antigens, Bacterial / Q000096:biosynthesis* / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D001483:Base Sequence; D015748:Borrelia burgdorferi Group / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D008074:Lipoproteins / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D015854:Up-Regulation
D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D004268:DNA-Binding Proteins; D008074:Lipoproteins; C118412:P35 protein, bacteria