ISSN:
1365-2958
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
,
Medicine
Notes:
The FruR regulator of Escherichia coli controls the initiation of transcription of several operons encoding a variety of proteins involved in carbon and energy metabolism. The sequence determinants of the FruR-binding site were analysed by using 6× His-tagged FruR and a series of double-stranded randomized oligonucleotides. FruR consensus binding sites were selected and characterized by several consecutive rounds of the polymerase chain reaction-assisted binding-site selection method (BSS) using nitrocellulose-immobilized DNA-binding protein. FruR was demonstrated to require, for binding, an 8 bp left half-site motif and a 3 bp conserved right half-site with the following sequence: 5′-GNNGAATC/GNT-3′. In this sequence, the left half-site AATC/ consensus tetranucleotide is a typical motif of the DNA-binding site of the regulators of the GalR–LacI family. On the other hand, the high degree of degeneracy found in the right half-site of this palindrome-like structure indicated that FruR, which is a tetramer in solution, interacts asymmetrically with the two half-sites of its operator. However, potentially FruR-target sites showing a high degree of symmetry were detected in 13 genes/operons. Among these, we have focused our interest on the pfkA gene, encoding phosphofructokinase-1, which is negatively regulated by FruR.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2958.1996.6341350.x
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