lprI Family assigned · medium auto-curated

H37Rv Rv1541c · MTBC0 mtbc0_001648 · 197 aa · 1753587–1754180 (-) · RefSeq NP_216057.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)lipoprotein LprI
MTBC0 PGAP re-annotationMliC family protein
Revised (this work)MliC family protein. Pfam: LprI (PF07007.18), MliC (PF09864.16).

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

Curated reference (UniProt)

UniProt P9WK41 SwissProt · reviewed · Evidence at protein level
UniProt nameLipoprotein LprI
Curated functionStrongly binds and inhibits lysozyme, may help bacteria survive in lysozyme-producing host cells. When overexpressed in M.tuberculosis or M.smegmatis increases resistance to hen egg white lysozyme. M.smegmatis overexpressing LprI survive better during intracellular infection of peritoneal and monocyte-derived macrophages, both of which produce lysozyme during infection; M.smegmatis does not encode this protein. Somewhat better survival is seen in human cell lines when M.smegmatis cells express both proteins from this operon, i.e. GlbN (HbN) and LprI.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namelprL
eggNOG descriptionLysozyme inhibitor LprI
Orthologous groupCOG4461
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 n/a
Polymorphic sites (≥ 0.1% of strains) 0 synonymous, 2 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)

PfamAccessioni-EvalueResiduesDescription
LprIPF07007.18 6.9e-0535–107 Lysozyme inhibitor LprI
MliCPF09864.16 9.2e-15125–190 Membrane-bound lysozyme-inhibitor of c-type lysozyme

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

Closest characterised functional partner: frdD (fumarate reductase membrane anchor subunit), medium confidence from genomic context alone (score 668 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1555 frdD fumarate reductase membrane anchor subunit 667 668 ctx cooccurence:666
Rv1542c glbN hemoglobin GlbN 697 661 ctx neighborhood:656
Rv1554 frdC fumarate reductase membrane anchor subunit 650 650 ctx cooccurence:649
Rv0240 vapC24 ribonuclease VapC24 634 635 ctx cooccurence:632
Rv2949c chorismate pyruvate-lyase 632 633 ctx cooccurence:631
Rv0613c hyp hypothetical protein 609 609 ctx cooccurence:608
Rv0355c PPE8 PPE family protein PPE8 600 600 ctx cooccurence:598
Rv1651c PE_PGRS30 PE-PGRS family protein PE_PGRS30 596 596 ctx cooccurence:596
Rv1917c PPE34 PPE family protein PPE34 592 592 ctx cooccurence:591
Rv3347c PPE55 PPE family protein PPE55 574 574 ctx cooccurence:573
Rv0304c PPE5 PPE family protein PPE5 573 573 ctx cooccurence:572
Rv3350c PPE56 PPE family protein PPE56 562 562 ctx cooccurence:562
Rv2490c PE_PGRS43 PE-PGRS family protein PE_PGRS43 562 562 ctx cooccurence:562
Rv2209 integral membrane protein 558 559 ctx cooccurence:557
Rv0341 iniB isoniazid inducible protein IniB 555 555 ctx cooccurence:555

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

  • Legacy H37Rv annotation: lipoprotein LprI
  • MTBC0 PGAP product: MliC family protein
  • Pfam (hmmscan --cut_ga): LprI PF07007.18 (E=7e-05), MliC PF09864.16 (E=9e-15)
  • (auto-curated by rules from PGAP + Pfam + Foldseek; not hand-reviewed)

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_216057.1)
  • Domains: Pfam-A via hmmscan --cut_ga — LprI (PF07007.18), MliC (PF09864.16)
  • 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 COG4461
  • Curated reference: UniProt P9WK41 (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 — 42 functional partner(s); context anchor frdD
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001648|Rv1541c|lprI
MRWIGVLVTALVLSACAANPPANTTSPTAGQSLDCTKPATIVQQLVCHDRQLTSLDHRLSTAYQQALAHRRSAALEAAQSSWTMLRDACAQDTDPRTCVQEAYQTRLVQLAIADPATATPPVLTYRCPTQDGPLTAQFYNQFDPKTAVLNWKGDQVIVFVELSGSGARYGRQGIEYWEHQGEVRLDFHGATFVCRTS