N-terminal sequence of phage lambda repressor

Summary Lambda repressor was purified from an E. coli strain which produces 150 times more lambda repressor than a single lysogen. The sequence of the fifty N-terminal residues was determined by automated Edman degradation. It contains 43% of all arginine and lysine residues of the chain and constitutes according to the genetic data of Oppenheim et al. (1975) a substantial part of the operator-DNA-binding site of the repressor.