title: Role of tryptophan 54 in the binding of E. coli single-stranded DNA-binding protein to single-stranded polynucleotides.
abstract: Fluorescence and optical detection of triplet state magnetic resonance spectroscopy have been employed to study the complexes formed by single-stranded polynucleotides with both E. coli single-stranded DNA-binding protein and an E. coli ssb gene product in which Trp-54 is replaced by phenylalanine using site specific oligonucleotide mutagenesis. Our results strongly suggest the involvement of Trp-54 in stabilizing the protein-nucleic acid complexes via stacking interactions of the aromatic residue with the nucleotide bases.
mesh_terms: D004268:DNA-Binding Proteins / Q000378:metabolism* / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics*; D049449:Luminescence; D011119:Polynucleotides / Q000378:metabolism*; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D004268:DNA-Binding Proteins; D011119:Polynucleotides