The width of the DNA minor groove varies with sequence and can be a major determinant of DNA shape recognition by proteins. For example, the minor groove within the center of the Fis-DNA complex narrows to about half the mean minor groove width of canonical B-form DNA to fit onto the protein surface. G/C base pairs within this segment, which is not contacted by the Fis protein, reduce binding a...

The designed peptide 1-methylimidazole-2-carboxamide netropsin (2-ImN) binds specifically to the sequence 5'-TGACT-3'. Direct evidence from NMR spectroscopy is presented that this synthetic ligand binds DNA as a 2:1 complex, which reveals that the structure is an antiparallel dimer in the minor groove of DNA. This is in contrast to the 1:1 complexes usually seen with most crescent-shaped minor ...

Protein-DNA binding is a fundamental component of gene regulatory processes, but it is still not completely understood how proteins recognize their target sites in the genome. Besides hydrogen bonding in the major groove (base readout), proteins recognize minor-groove geometry using positively charged amino acids (shape readout). The underlying mechanism of DNA shape readout involves the correl...

The sequence logo for DNA binding sites of the bacteriophage P1 replication protein RepA shows unusually high sequence conservation ( approximately 2 bits) at a minor groove that faces RepA. However, B-form DNA can support only 1 bit of sequence conservation via contacts into the minor groove. The high conservation in RepA sites therefore implies a distorted DNA helix with direct or indirect co...

The MogR transcriptional repressor of the intracellular pathogen Listeria monocytogenes recognizes AT-rich binding sites in promoters of flagellar genes to downregulate flagellar gene expression during infection. We describe here the 1.8 A resolution crystal structure of MogR bound to the recognition sequence 5' ATTTTTTAAAAAAAT 3' present within the flaA promoter region. Our structure shows tha...

A theoretical investigation is performed of the complexes of a tetracationic porphyrin, tetra-(4-N-methylpyridyl)-porphyrin, (T4MPyP), with the hexanucleotides d(CGCGCG)2 and d(TATATA)2, considering the possibility of both the intercalative and the groove binding interactions. These computations demonstrate that T4MPyP manifests a significant preference for intercalation in its complex with d(C...

Cluster of differentiation 1c (CD1c)-dependent self-reactive T cells are abundant in human blood, but self-antigens presented by CD1c to the T-cell receptors of these cells are poorly understood. Here we present a crystal structure of CD1c determined at 2.4 Å revealing an extended ligand binding potential of the antigen groove and a substantially different conformation compared with known CD1c ...

The AcrB trimeric multidrug efflux transporter of Escherichia coli pumps out a very wide spectrum of compounds. Although minocycline and doxorubicin have been cocrystallized within the large binding pocket in the periplasmic domain of the binding protomer, nothing is known about the binding of many other ligands to this protein. We used computer docking to evaluate the interaction of about 30 c...

Two new crescent-shaped unsymmetrical cyanine dyes have been synthesised and their interactions with DNA have been investigated by different spectroscopic methods. These dyes are analogues to a minor groove binding unsymmetrical cyanine dye, BEBO, recently reported by us. In this dye, the structure of the known intercalating cyanine dye BO was extended with a benzothiazole substituent. To inves...

We compare the fluorescence properties of bisbenzimide (also known as Hoechst 33258) bound to the minor groove of the poly[d(AT)].poly[d(AT)] duplex with the corresponding fluorescence properties of bisbenzimide dissolved in neat organic solvents and mixed organic/aqueous solvents. Based on these comparisons, we conclude that the minor groove of the bisbenzimide-poly[d(AT)].poly[d(AT)] complex ...