Script: compare_ecf41_relatives.py (output in compare_ecf41_relatives.out). Sequences fetched
live from UniProt REST; global Needleman-Wunsch alignment, BLOSUM62, gap open -10 / extend -0.5.
Results
| Pair |
Full-length identity |
N-terminal sigma2/sigma4 region (1-170) |
C-terminal extension |
| Q9KZ33 vs P9WGH3 (Mtb SigI, same PANTHER subfamily SF43) |
33.0% (273 cols) |
34.2% |
31.2% |
| Q9KZ33 vs L0TCG5 (Mtb SigJ, PANTHER SF36, IBA seed) |
34.7% (271 cols) |
35.0% |
34.2% |
Interpretation
- Q9KZ33 aligns over essentially its full length (~270 of 300 residues) to both Mtb ECF41 sigma
factors, including the ~130-residue C-terminal extension. The UniProt record lists an NTF2-like
superfamily match (SSF54427; IPR032710) for this extension, the same fold class (SnoaL_2) that
defines the C-terminal regulatory extension of group ECF41 sigma factors.
- Pairwise identity does not discriminate SigI from SigJ (both ~33-35%); the subfamily placement
(SF43 with SigI) therefore rests on PANTHER's HMM classification, not on this pairwise check.
- No residue-level conclusion about activity is drawn; the sigma2 and sigma4 regions are intact by
InterPro/SUPFAM matches (IPR052704, IPR013324, SSF88659).