Sunanda Deb

  • Citations Per Year
Learn More
Binding of regulatory proteins to multipartite DNA binding sites often occurs with protein-protein interaction, resulting in cooperative binding. The operators of bacteriophage lambda have several pairs of repressor binding sites (O(R)1-O(R)2, O(R)2-O(R)3, O(L)1-O(L)2, and O(L)2-O(L)3) separated by a variable number of base pairs, and thus, bacteriophage(More)
A site-directed mutation, F235C, was created at the penultimate residue of the lambda-repressor. Measurement of dimer-monomer dissociation constant suggested that dimer-monomer dissociation of the mutant repressor is similar to that of the wild-type. Affinity towards a single operator O(R)1 is also similar to that of the wild-type repressor. The mutant(More)
A non-cooperative mutant of lambda-repressor, Y210C, has been purified and characterized. The mutant protein does not show any evidence of cooperative interaction as judged by difference near-UV circular dichroism spectra of DNA. The mutant protein also shows much weaker self-assembly as revealed by fluorescence anisotropy measurement. The far-UV circular(More)
Nandan K.Jana1, Sunanda Deb2, Bhabatarak In this regulatory system, λ-repressor binds to several pairs of operator sites (e.g. OR1–OR2, OL1–OL2) with concomitant Bhattacharyya1, Nitai C.Mandal1 and Siddhartha Roy2,3 interaction between two adjacent site bound dimers. Primarily 1Department of Biochemistry and 2Department of Biophysics, Bose due to work of(More)
A lambda-repressor mutant, S228N, which is defective in tetramer formation in the free state but retains full cooperativity, was studied in detail. Isolated single operator-bound S228N repressor shows association properties similar to those of the wild-type repressor. Fluorescence anisotropy studies with dansyl chloride-labeled repressor show a(More)
Stability and induction of the lysogenic state of bacteriophage λ are balanced by a complex regulatory network. A key feature of this network is the mutually exclusive cooperative binding of a repressor dimer (CI) to one of two pairs of binding sites, O(R)1-O(R)2 or O(R)2-O(R)3. The structural features that underpin the mutually exclusive binding mode are(More)
  • 1