Mutational analysis of DNaseI-DNA-interactions

Protein-DNA interactions at a dioxin-responsive enhancer. Mutational analysis of the DNA-binding site for the liganded Ah receptor.

The liganded Ah receptor activates transcription by binding to a specific DNA-recognition motif within a dioxin-responsive enhancer upstream of the CYP1A1 gene. Analyses of mutant enhancers by gel retardation reveal that each base pair within the domain 5'CGTG(GCAC)3' is essential to the receptor-enhancer interaction. The three base pairs immediately flanking each end of the essential domain co...

Mutational analysis of conserved residues in HhaI DNA methyltransferase.

HhaI DNA methyltransferase belongs to the C5-cytosine methyltransferase family, which is characterized by the presence of a set of highly conserved amino acids and motifs present in an invariant order. HhaI DNA methyltransferase has been subjected to a lot of biochemical and crystallographic studies. A number of issues, especially the role of the conserved amino acids in the methyltransferase a...

Nature of Lithium Interactions with DNA Nucleobases: Theoretical Study

In the present study, the interactions of three different lithium species Li+, Li3+ and CH3Li with several different sites of the most stable tautomers of DNA nucleo-bases are presented. This investigation is based on the results of thermochemical properties, Quantum Theory of Atoms in Molecules (QTAIM) and Natural Bond Orbi...

Chlorella virus DNA ligase: nick recognition and mutational analysis.

Chlorella virus PBCV-1 DNA ligase seals nicked DNA substrates consisting of a 5'-phosphate-terminated strand and a 3'-hydroxyl-terminated strand annealed to a bridging DNA template strand. The enzyme discriminates at the DNA binding step between substrates containing a 5'-phosphate versus a 5'-hydroxyl at the nick. Mutational analysis of the active site motif KxDGxR (residues 27-32) illuminates...

Analysis of Protein Interactions Controlling DNA Methyltransferases