Table 1.
Anabaena sigma factors used in this study. Percent amino acid identity/similarity compared to E. coli K-12 substr. MG1655 as determined by BLAST analysis (blastp algorithm). The E. coli sigma factor used for comparison is listed in parentheses. *Identified using PSI-BLAST. Sigma factor adapted from Bell, Lee and Summers (2017).
| Sigma factor | Group | Mass (kDa) | % Amino acid identity/similarity to E. coli σ factors |
|---|---|---|---|
| All5263 (SigA) | 1 | 46.7 | 59/77 (RpoD) |
| All7615 (SigB) | 2 | 38.4 | 44/68 (RpoD) |
| Alr3800 (SigB2) | 37.9 | 46/73 (RpoD) | |
| All7608 (SigB3) | 38.0 | 41/69 (RpoD) | |
| All7179 (SigB4) | 36.4 | 42/68 (RpoD) | |
| All1692 (SigC) | 47.4 | 48/71 (RpoD) | |
| Alr3810 (SigD) | 37.6 | 46/69 (RpoD) | |
| Alr4249 (SigE) | 45.4 | 45/69 (RpoD) | |
| All3853 (SigF) | 3 | 30.0 | 26/50 (RpoD) |
| Alr0277 (SigJ) | 30.0 | 28/48 (FliA) | |
| Alr3280 (SigG) | 4 | 25.2 | 34/52 (RpoE) |
| All2193 (SigI) | 22.6 | 26/44 (RpoE)* |