Abstract
The galactose operon of Streptococcus mutans is transcriptionally regulated by a repressor protein (GalR) encoded by the galR gene, which is divergently oriented from the structural genes of the gal operon. To study the regulatory function of GalR, we partially purified the protein and examined its DNA binding activity by gel mobility shift and DNase I footprinting experiments. The protein specifically bound to the galR-galK intergenic region at an operator sequence, the position of which would suggest that GalR plays a role in the regulation of the gal operon as well as autoregulation. To further examine this hypothesis, transcriptional start sites of the gal operon and the galR gene were determined. Primer extension analysis showed that both promoters overlap the operator, indicating that GalR most likely represses transcription initiation of both promoters. Finally, the results from in vitro binding experiments with potential effector molecules suggest that galactose is a true intracellular inducer of the galactose operon.
| Original language | English |
|---|---|
| Pages (from-to) | 5727-5732 |
| Number of pages | 6 |
| Journal | Journal of Bacteriology |
| Volume | 180 |
| Issue number | 21 |
| State | Published - Nov 1 1998 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Applied Microbiology and Biotechnology
- Immunology
Cite this
Transcriptional regulation of the Streptococcus mutans gal operon by the GalR repressor. / Ajdic, Dragana; Ferretti, Joseph J.
In: Journal of Bacteriology, Vol. 180, No. 21, 01.11.1998, p. 5727-5732.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Transcriptional regulation of the Streptococcus mutans gal operon by the GalR repressor
AU - Ajdic, Dragana
AU - Ferretti, Joseph J.
PY - 1998/11/1
Y1 - 1998/11/1
N2 - The galactose operon of Streptococcus mutans is transcriptionally regulated by a repressor protein (GalR) encoded by the galR gene, which is divergently oriented from the structural genes of the gal operon. To study the regulatory function of GalR, we partially purified the protein and examined its DNA binding activity by gel mobility shift and DNase I footprinting experiments. The protein specifically bound to the galR-galK intergenic region at an operator sequence, the position of which would suggest that GalR plays a role in the regulation of the gal operon as well as autoregulation. To further examine this hypothesis, transcriptional start sites of the gal operon and the galR gene were determined. Primer extension analysis showed that both promoters overlap the operator, indicating that GalR most likely represses transcription initiation of both promoters. Finally, the results from in vitro binding experiments with potential effector molecules suggest that galactose is a true intracellular inducer of the galactose operon.
AB - The galactose operon of Streptococcus mutans is transcriptionally regulated by a repressor protein (GalR) encoded by the galR gene, which is divergently oriented from the structural genes of the gal operon. To study the regulatory function of GalR, we partially purified the protein and examined its DNA binding activity by gel mobility shift and DNase I footprinting experiments. The protein specifically bound to the galR-galK intergenic region at an operator sequence, the position of which would suggest that GalR plays a role in the regulation of the gal operon as well as autoregulation. To further examine this hypothesis, transcriptional start sites of the gal operon and the galR gene were determined. Primer extension analysis showed that both promoters overlap the operator, indicating that GalR most likely represses transcription initiation of both promoters. Finally, the results from in vitro binding experiments with potential effector molecules suggest that galactose is a true intracellular inducer of the galactose operon.
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UR - http://www.scopus.com/inward/citedby.url?scp=0031795805&partnerID=8YFLogxK
M3 - Article
C2 - 9791125
AN - SCOPUS:0031795805
VL - 180
SP - 5727
EP - 5732
JO - Journal of Bacteriology
JF - Journal of Bacteriology
SN - 0021-9193
IS - 21
ER -