title: The lambda repressor contains two domains.
abstract: Papain digestion of the lambda phage repressor produces two fragments that are relatively resistant to further digestion. One includes the amino terminus (residues 1-92) and the other the carboxyl terminus (residues 132-236). Calorimetry shows that the amino-terminal fragment denatures near 50 degrees C and that the carboxyl-terminal fragment denatures near 70 degrees C. Intact repressor undergoes two denaturations, one near 50 degrees C and another near 70 degrees C. These and other data show that lambda repressor consists of two domains joined by a "connector" 40 amino acids long that is sensitive to proteases. The amino-terminal domain binds DNA, and the carboxyl-terminal domain oligomerizes.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D003090:Coliphages / Q000032:analysis*; D008970:Molecular Weight; D010206:Papain; D010446:Peptide Fragments / Q000032:analysis; D011489:Protein Denaturation; D012097:Repressor Proteins; D014157:Transcription Factors
chemical_list: D000596:Amino Acids; D010446:Peptide Fragments; D012097:Repressor Proteins; D014157:Transcription Factors; D010206:Papain