CV_2726 (Q7NUH2): comparison with characterized PTHR33164:SF43 members
Script: compare_sf43_members.py (run with uv run compare_sf43_members.py); raw output in RESULTS-output.txt.
Global Needleman-Wunsch alignment, BLOSUM62, gap open -10 / extend -0.5; identity is computed over the shorter sequence.
PANTHER placements are read live from UniProt.
Results
| Accession |
Protein |
PANTHER |
Identity to Q7NUH2 |
| P9WME9 |
Rv2887, M. tuberculosis |
PTHR33164:SF43 |
28.8% |
| O33817 |
HcrR-like, Thauera aromatica |
PTHR33164:SF43 |
27.2% |
| Q9F4G3 |
TcaR, S. aureus COL |
PTHR33164:SF43 |
20.4% |
| P70993 |
YwhA, B. subtilis |
PTHR33164:SF43 |
20.1% |
| P27245 |
MarR, E. coli (outgroup) |
PTHR33164:SF87 |
24.3% |
| O31541 |
YetL, B. subtilis |
PTHR42756:SF1 |
21.1% |
Interpretation
- Q7NUH2 is placed in PTHR33164:SF43, which is named "HTH-TYPE TRANSCRIPTIONAL REPRESSOR YETL".
UniProt now places B. subtilis YetL itself in a different family (PTHR42756:SF1). The subfamily name
is therefore a historical label and says nothing about the CV_2726 ligand (YetL responds to flavonoids).
- Inside SF43, CV_2726 shares only 20-29% identity with the characterized members. That is about the same
as its identity to E. coli MarR, which sits in a different subfamily (SF87). SF43 is a broad grouping, and
the identities do not single out an ortholog. Rv2887 is the closest characterized SF43 member (28.8%):
it represses the htm (Rv0560c) methyltransferase gene and is released from DNA by salicylate and
para-aminosalicylate. At this identity, neither the regulon nor the ligand can be transferred to CV_2726.
- KEGG genomic neighbourhood: CV_2722 acyl-CoA hydrolase, CV_2723 acyl-CoA dehydrogenase, CV_2724 TetR
regulator, CV_2725 metZ, CV_2727 conserved hypothetical protein, CV_2728 alcohol dehydrogenase, CV_2729 MarC.
None of these clearly marks a regulon. Strand and operon structure were not analysed.
- C. violaceum OhrR (CV_0210, Q7P1K3; found by UniProt query on 2026-10-21) is placed in PTHR33164:SF5, not SF43,
so it is a paralog in a different subfamily. Its organic-hydroperoxide-sensing role is not transferred to CV_2726.