title: Dynamic filtering by two-dimensional 1H NMR with application to phage lambda repressor.
abstract: Flexible regions of proteins play an important role in catalysis, ligand binding, and macromolecular interactions. Because of its enhanced sensitivity to motional narrowing, two-dimensional coupling constant J-correlated 1H NMR may be used to observe these regions selectively. Dynamic filtering is an intrinsic feature of this experiment because cross-peak amplitude decays rapidly as linewidths approach the coupling constant. We demonstrate here the flexibility of the NH2-terminal arm of phage lambda repressor, which is thought to wrap around the double helix in the repressor-operator complex. The assignment of arm resonances is made possible by the construction of mutant repressor genes containing successive NH2-terminal deletions.
mesh_terms: D010582:Bacteriophage lambda / Q000235:genetics*; D011088:DNA Ligases; D004926:Escherichia coli / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009154:Mutation; D011487:Protein Conformation; D012097:Repressor Proteins; D014157:Transcription Factors
chemical_list: D012097:Repressor Proteins; D014157:Transcription Factors; D011088:DNA Ligases