Temperature-dependence of open-complex formation at two Escherichia coli promoters with extended -10 sequences.
We have studied the formation of open complexes between purified RNA polymerase from Escherichia coli and DNA fragments carrying the galP1 promoter, a promoter with an extended -10 region. Unusually, these complexes are formed readily at low temperatures. This low-temperature opening is unaffected by deletions of either upstream or downstream promoter sequences. We conclude that low-temperature open-complex formation is due to specific base sequences in and just upstream of the extended -10 region. In contrast, open complexes are not formed at low temperatures with DNA fragments carrying the E. coli cysG promoter, which also has an extended -10 region. This demonstrates that an extended -10 sequence alone is not sufficient for low-temperature opening. Additionally, we report the temperature dependence of a hybrid galP1-cysG promoter, the related galP2 and galP3 promoters and a derivative of galP1 with an improved -10 hexamer sequence.
Burns
H D
HD
School of Biochemistry, University of Birmingham, U.K.
Belyaeva
T A
TA
Busby
S J
SJ
Minchin
S D
SD
D001483:Base Sequence; D018983:DNA Footprinting; D004269:DNA, Bacterial / Q000378:metabolism; D004278:DNA, Superhelical / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D005690:Galactose / Q000378:metabolism; D008780:Methyltransferases / Q000235:genetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009876:Operon; D011196:Potassium Permanganate; D011401:Promoter Regions, Genetic; D013696:Temperature; D014158:Transcription, Genetic
D004269:DNA, Bacterial; D004278:DNA, Superhelical; D011196:Potassium Permanganate; D008780:Methyltransferases; C060508:uroporphyrin-III C-methyltransferase; D012321:DNA-Directed RNA Polymerases; D005690:Galactose