Rv1823 Family assigned · low
H37Rv Rv1823 · MTBC0 mtbc0_001937 ·
307 aa · 2087790–2088713 (+) ·
RefSeq NP_216339.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | hypothetical protein |
|---|---|
| MTBC0 PGAP re-annotation | DUF881 domain-containing protein |
| Revised (this work) | Small coiled-coil membrane protein, candidate divisome / cell-division-associated component (FtsB/FtsL-like); paralog of the uncharacterized Rv1825; coiled-coil fold limits confidence RefSeq leaves this locus uncharacterised. |
Curated reference (UniProt)
| UniProt |
P9WFG1
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | UPF0749 protein Rv1823 |
UniProt still lists this protein as UPF0749 protein Rv1823; the revised annotation above is ahead of the current UniProt record.
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
S Function unknown
|
|---|---|
| eggNOG description | Bacterial protein of unknown function (DUF881) |
| Orthologous group | COG3879 |
| Gene Ontology (12) |
GO:0005575, GO:0005623, GO:0005886, GO:0005887, GO:0016020, GO:0016021, GO:0031224, GO:0031226, GO:0044425, GO:0044459, GO:0044464, GO:0071944
|
Orthology-based transfer (eggNOG 5.0.2, diamond). EC/KO/GO/CAZy are computed annotations, not manual curation; cross-check against the primary literature before treating a specific reaction as established.
Conservation & selection (intra-MTBC, 145 209 strains)
| pN/pS | 0.495 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 3 synonymous, 4 missense, 0 nonsense, 0 frameshift |
pN/pS from segregating SNPs (singletons removed) normalised by possible sites. Low pN/pS = purifying selection (a strong signal that a "hypothetical" is a real, constrained gene). A high pN/pS is ambiguous: relaxed constraint or positive selection (drug resistance, antigenic variation) inflate it; e.g. rpoB/katG/pncA score high here for resistance, not loss of function. A clonal disruption (one allele over a clade) suggests lineage pseudogenisation; a convergent one (many independent alleles) is typical of resistance loss-of-function.
Domains (Pfam, hmmscan --cut_ga)
| Pfam | Accession | i-Evalue | Residues | Description |
|---|---|---|---|---|
DUF881 | PF05949.18 | 1.3e-34 | 150–303 | Bacterial protein of unknown function (DUF881) |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: pgsA2 (CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase), high confidence from genomic context alone (score 883 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv1824 hyp |
hypothetical protein | 992 | 992 ctx | neighborhood:839 cooccurence:774 coexpression:797 |
Rv1822 pgsA2 |
CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase | 883 | 883 ctx | neighborhood:882 |
Rv1825 hyp |
hypothetical protein | 921 | 882 ctx | neighborhood:822 |
Rv1826 gcvH |
glycine cleavage system protein H | 781 | 781 ctx | neighborhood:778 |
Rv1821 secA2 |
accessory Sec system translocase SecA2 | 738 | 738 ctx | neighborhood:736 |
Rv3300c hyp |
hypothetical protein | 738 | 738 | coexpression:738 |
Rv1820 ilvG |
acetolactate synthase large subunit IlvG | 728 | 729 ctx | neighborhood:728 |
Rv1828 |
HTH-type transcriptional regulator | 684 | 684 ctx | neighborhood:676 |
Rv1827 garA |
glycogen accumulation regulator GarA | 657 | 656 ctx | neighborhood:653 |
Rv1819c bacA |
vitamin B12 transport ATP-binding protein BacA | 651 | 652 ctx | neighborhood:650 |
Rv1829 hyp |
hypothetical protein | 904 | 537 ctx | neighborhood:527 textmining:803 |
Rv1009 rpfB |
resuscitation-promoting factor RpfB | 466 | 466 ctx | cooccurence:457 |
Rv3301c phoY1 |
phosphate transport system transcriptional regulator PhoY | 457 | 458 | coexpression:458 |
Rv2375 hyp |
hypothetical protein | 448 | 448 ctx | cooccurence:447 |
Rv2612c pgsA1 |
CDP-diacylglycerol--inositol 3-phosphatidyltransferase | 675 | 174 | textmining:623 |
STRING combines evidence channels (neighborhood, fusion, cooccurrence, coexpression, experimental, database, text-mining) into a 0–1000 score. The ctx badge marks edges carried by the genomic-context channels (conserved neighborhood, fusion, phylogenetic co-occurrence), which are independent of orthology and structure and the strongest signal for an unknown gene. The no text-mining column recomputes the score from data alone, so a link that does not depend on the literature is visible. Association is a function hypothesis, not proof: corroborate with the operon context and the primary literature before assigning a function.
Evidence
- HHpred: top hit paralog Rv1825 (uncharacterized) 100% E1.2e-35; then divisome FtsB/FtsL 94-96% + M.tb cell-division/PG proteins (MctB, RipA, NlpC/P60) - above the coiled-coil de-novo-peptide noise floor (90-93%)
- HHpred web (MPI Bioinformatics Toolkit, profile-profile remote homology), interpreted in project 'Still unknown gene function', 2026-06-10. A fold/family-level assignment, not a demonstrated function.
Sources
- Ancestral sequence & coordinates: Harrison LB et al. (2024), An imputed ancestral reference genome for the MTBC, doi:10.1101/2023.09.07.556366
- Product annotation: NCBI PGAP on MTBC0; legacy from H37Rv NC_000962.3 (RefSeq NP_216339.1)
- Domains: Pfam-A via hmmscan --cut_ga — DUF881 (PF05949.18)
- Sequence-level signal: ESM Atlas (EvolutionaryScale × BioHub) — exploratory
- Controlled vocabulary: eggNOG-mapper 2.1.12 (Cantalapiedra et al. 2021,
doi:10.1093/molbev/msab293), eggNOG 5.0 DB
(Huerta-Cepas et al. 2019) — OG
COG3879 - Curated reference: UniProt P9WFG1 (SwissProt, reviewed; Evidence at protein level)
- Intra-MTBC selection: pN/pS and disruption from SPDI variants of 145 209 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
- Model confidence: ESMFold per-residue pLDDT (mean 88.0, confident)
- Interaction network: STRING v12.0 (Szklarczyk et al. 2023,
doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 —
22 functional partner(s); context anchor
pgsA2 - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_001937|Rv1823| MAESDRLLGGYDPNAGYSAHAGAQPQRIPVPSLLRALLSEHLDAGYAAVAAERERAAAPRCWQARAVSWMWQALAATLVAAVFAAAVAQARSVAPGVRAAQQLLVASVRSTQAAATTLAQRRSTLSAKVDDVRRIVLADDAEGQRLLARLDVLSLAAASAPVVGPGLTVTVTDPGASPNLSDVSKQRVSGSQQIILDRDLQLVVNSLWESGAEAISIDGVRIGPNVTIRQAGGAILVDNNPTSSPYTILAVGPPHAMQDVFDRSAGLYRLRLLETSYGVGVSVNVGDGLALPAGATRDVKFAKQIGP