lppW Family assigned · medium

H37Rv Rv2905 · MTBC0 mtbc0_003087 · 314 aa · 3235457–3236401 (+) · RefSeq NP_217421.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)lipoprotein LppW
MTBC0 PGAP re-annotationhypothetical protein
Revised (this work)Serine-hydrolase of the class A beta-lactamase / penicillin-binding fold. RefSeq leaves it 'lipoprotein LppW'. Two independent signals converge: eggNOG annotates a 'Beta-lactamase' orthologous group (COG V, defense), and the AlphaFold model superposes on the class A beta-lactamase PenL (PDB 5gld; Foldseek prob 1.0, E 8e-10, TM 0.71). A locus distinct from the canonical M. tuberculosis beta-lactamase BlaC (Rv2068c); the Ser-x-x-Lys catalytic motif and the substrate are not demonstrated here.

Curated reference (UniProt)

UniProt P9WK67 SwissProt · reviewed · Evidence at protein level
UniProt namePutative lipoprotein LppW

UniProt still lists this protein as Putative lipoprotein LppW; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category V Defense mechanisms
Preferred namelppW
eggNOG descriptionBeta-lactamase
Orthologous groupCOG2367
Gene Ontology (2) GO:0005575, GO:0005576

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 0.287 · purifying
Polymorphic sites (≥ 0.1% of strains) 5 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)

No Pfam-A domain above the gathering threshold (or not yet scanned).

Functional interaction network (STRING v12, guilt-by-association)

Closest characterised functional partner: eccD3 (ESX-3 secretion system protein EccD), medium confidence from genomic context alone (score 638 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1836c hyp hypothetical protein 698 698 ctx cooccurence:683
Rv3906c hyp hypothetical protein 684 685 ctx cooccurence:666
Rv0290 eccD3 ESX-3 secretion system protein EccD 637 638 ctx cooccurence:636
Rv1698 mctB copper transporter MctB 623 624 ctx cooccurence:618
Rv0518 hyp hypothetical protein 592 593 ctx cooccurence:588
Rv0990c hyp hypothetical protein 555 556 ctx cooccurence:554
Rv0472c HTH-type transcriptional regulator 550 551 ctx cooccurence:544
Rv0499 hyp hypothetical protein 547 548 ctx cooccurence:526
Rv1118c hyp hypothetical protein 520 521 ctx cooccurence:518
Rv1639c hyp hypothetical protein 521 519 ctx cooccurence:504
Rv3587c membrane protein 514 515 ctx cooccurence:508
Rv3810 pirG cell surface protein 512 512 ctx cooccurence:507
Rv2091c membrane protein 508 508 ctx cooccurence:503
Rv0517 acyltransferase 501 501 ctx cooccurence:501
Rv0010c membrane protein 496 497 ctx cooccurence:492

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

  • eggNOG OG 'Beta-lactamase', COG V (defense)
  • Foldseek -> class A beta-lactamase PenL (5gld), prob 1.0, E 8e-10, TM 0.71
  • Distinct locus from BlaC/Rv2068c (fold-paralogue safeguard)
  • Structural homology: AlphaFold DB model + Foldseek vs PDB (project 'Still unknown gene function', phase5-7, 2026-06-10). A fold-level family assignment, not a demonstrated activity.

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_217421.1)
  • Domains: Pfam-A via hmmscan --cut_ga — none above threshold
  • 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 COG2367
  • Curated reference: UniProt P9WK67 (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)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 40 functional partner(s); context anchor eccD3
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003087|Rv2905|lppW
MRARPLTLLTALAAVTLVVVAGCEARVEAEAYSAADRISSRPQARPQPQPVELLLRAITPPRAPAASPNVGFGELPTRVRQATDEAAAMGATLSVAVLDRATGQLVSNGNTQIIATASVAKLFIADDLLLAEAEGKVTLSPEDHHALDVMLQSSDDGAAERFWSQDGGNAVVTQVARRYGLRSTAPPSDGRWWNTISSAPDLIRYYDMLLDGSGGLPLDRAAVIIADLAQSTPTGIDGYPQRFGIPDGLYAEPVAVKQGWMCCIGSSWMHLSTGVIGPERRYIMVIESLQPADDATARATITQAVRTMFPNGRI