Table 1.
The six operator sites recognized by λ-repressor and Cro
| Operator | Sequence
|
|
|---|---|---|
| Consensus half | Nonconsensus half | |
| OR1 | 5′ T A T C A C C G C C A G A G G T A 3′ A T A G T G G C G G T C T C C A T | |
| OR2 | 5′ T A A C A C C G T G C G T G T T G 3′ A T T G T G G C A C G C A C A A C | |
| OR3 | 5′ T A T C A C C G C A A G G G A T A 3′ A T A G T G G C G T T C C C T A T | |
| OL1 | 5′ T A T C A C C G C C A G T G G T A 3′ A T A G T G G C G G T C A C C A T | |
| OL2 | 5′ C A A C A C C G C C A G A G A T A 3′ G T T G T G G C G G T C T C T A T | |
| OL3 | 5′ T A T C A C C G C A G A T G G T T 3′ A T A G T G G C G T C T A C C A A | |
| Consensus | 5′ T A T C A C C G C C A G T G G T A 3′ A T A G T G G C G G T C A C C A T | |
| Number of occurrences | 5 6 4 6 6 6 6 6 5 3 4 5 3 6 3 6 4 | |
| Position | 1 2 3 4 5 6 7 8 9 8′ 7′ 6′ 5′ 4′ 3′ 2′ 1′ | |
The sequences of the six operator sites are from Ptashne (2) with OL2 aligned so that the bps contacted by the amino-terminal arm of λ-repressor lie in the consensus half, as is the case for all the other operators.