Lambda phage protein Nu 1 contains the conserved DNA binding fold of repressors.

Analysis of 64 lambda phage proteins revealed the presence of four strong variants of the conserved DNA binding fold of repressors. Three of them have been known from previous studies but the Nu 1 gene product is a new member of the family of proteins that may bind strongly to DNA in the repressor-like fashion. It is peculiar that the motif occurs in the very N terminus of Nu 1 just between two possible starts of its gene.