TABLE 1.
Chimeric Nu1 alleles used in this study
| Allele (motif segment origin)a | Remarks | Reference |
|---|---|---|
| Nu1hy51 (H21 T21H21 w21) | Codons 1–103 derived from small terminase subunit gene 1 of phage 21. | Frackman et al.(1985) |
| Nu1hy1 (Hλ TλH21 w λ) | Produces gpNu1 with the four amino acids of the recognition helix replaced with those of 21's gp1. | de Beer et al. (2002) |
| Nu1hy2 (H21 T21H21 w λ) | Codons 1–24 derived from phage 21's 1 gene. Small subunit residues derived from phage 21's gp1 include the amino terminus and the helix-turn-helix motif. | de Beer et al. (2002) |
| Nu1hy3 (H21 TλH21 w λ) | Small subunit differs from gpNu1 by two amino acids of the support helix and four amino acids of the recognition helix being replaced with those of 21's gp1. | This work |
|
Nu1hy4 (Hλ T21H21 w λ) |
Small subunit differs from gpNu1 in four amino acids of the recognition helix and three amino acids of the turn being replaced with those of 21's gp1. |
This work |
a
Origins of gpNu1 segments of the winged helix-turn-helix DNA-binding motif, as described in materials and methods.