title: Homology among DNA-binding proteins suggests use of a conserved super-secondary structure.
abstract: The amino acid sequences of the repressor and cro proteins of phages lambda, 434 and P22 are homologous, especially in a region in which repressor and lambda cro have a similar alpha-helix-turn-alpha-helix secondary structure. Model-building studies indicate that this structure is important in DNA binding, and we suggest it may be a common feature of many DNa-binding proteins.
mesh_terms: D000595:Amino Acid Sequence; D001435:Bacteriophages; D005075:Biological Evolution; D002352:Carrier Proteins / Q000032:analysis*; D004269:DNA, Bacterial / Q000378:metabolism; D004268:DNA-Binding Proteins; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D012097:Repressor Proteins / Q000032:analysis*; D014157:Transcription Factors / Q000032:analysis*; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D002352:Carrier Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; C016649:phage repressor proteins