mmpL8 Resolved · high auto-curated

H37Rv Rv3823c · MTBC0 mtbc0_004052 · 1089 aa · 4312370–4315639 (-) · RefSeq NP_218340.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)integral membrane transport protein MmpL8
MTBC0 PGAP re-annotationsulfolipid-1 RND transporter MmpL8
Revised (this work)Sulfolipid-1 RND transporter MmpL8. Pfam: MMPL (PF03176.22), Sterol-sensing (PF12349.15).

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

Curated reference (UniProt)

UniProt P9WJU5 SwissProt · reviewed · Evidence at protein level
UniProt nameSulfolipid-1 exporter MmpL8
Curated functionRequired for the biosynthesis and the transport across the inner membrane of sulfolipid-1 (SL-1), which is a major cell wall lipid of pathogenic mycobacteria. Could also transport SL1278 (2-palmitoyl-3-(C43)-phthioceranyl-alpha, alpha'-D-trehalose-2'-sulfate), which is the precursor of SL-1. Required for virulence.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namemmpL10
eggNOG descriptiontransport protein
Orthologous groupCOG1511
KEGG orthology K06994
Gene Ontology (30) GO:0005575, GO:0005618, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0006082, GO:0006629, GO:0006790, GO:0008150, GO:0008152, GO:0008610 +18 more

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 0.379 · purifying
Polymorphic sites (≥ 0.1% of strains) 14 synonymous, 15 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
MMPLPF03176.22 3.2e-10775–401 MMPL family
Sterol-sensingPF12349.15 2.6e-05240–375 Sterol-sensing domain of SREBP cleavage-activation

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

Closest characterised functional partner: papA1 (acyltransferase), high confidence from genomic context alone (score 937 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3824c papA1 acyltransferase 994 937 ctx neighborhood:535 coexpression:803 textmining:915
Rv3825c pks2 phthioceranic/hydroxyphthioceranic acid synthase 969 862 ctx neighborhood:436 coexpression:737 textmining:791
Rv1183 mmpL10 transmembrane transport protein MmpL10 813 808 coexpression:803
Rv1598c hyp hypothetical protein 562 562 ctx cooccurence:562
Rv1303 hyp hypothetical protein 507 507 ctx cooccurence:507
Rv1145 mmpL13a transmembrane transport protein 550 500 ctx cooccurence:497
Rv1182 papA3 acyltransferase papA3 881 484 textmining:779
Rv0523c hyp hypothetical protein 407 408 ctx cooccurence:406
Rv3826 fadD23 long-chain-fatty-acid--CoA ligase FadD23 665 380 textmining:482
Rv3820c papA2 trehalose-2-sulfate acyltransferase 813 368 textmining:717
Rv2942 mmpL7 transmembrane transport protein MmpL7 455 323
Rv0383c ttfA hyp hypothetical protein 411 298
Rv1184c chp2 hyp hypothetical protein 414 293
Rv0295c stf0 hyp hypothetical protein 628 244 textmining:528
Rv1181 pks4 polyketide beta-ketoacyl synthase 750 217 textmining:695

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: integral membrane transport protein MmpL8
  • MTBC0 PGAP product: sulfolipid-1 RND transporter MmpL8
  • Pfam (hmmscan --cut_ga): MMPL PF03176.22 (E=3e-107), Sterol-sensing PF12349.15 (E=3e-05)
  • (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_218340.1)
  • Domains: Pfam-A via hmmscan --cut_ga — MMPL (PF03176.22), Sterol-sensing (PF12349.15)
  • 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 COG1511
  • Curated reference: UniProt P9WJU5 (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 — 23 functional partner(s); context anchor papA1
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_004052|Rv3823c|mmpL8
MCDVLMQPVRTPRPSTNLRSKPLRPTGDGGVFPRLGRLIVRRPWVVIAFWVALAGLLAPTVPSLDAISQRHPVAILPSDAPVLVSTRQMTAAFREAGLQSVAVVVLSDAKGLGAADERSYKELVDALRRDTRDVVMLQDFVTTPPLRELMTSKDNQAWILPVGLPGDLGSTQSKQAYARVADIVEHQVAGSTLTANLTGPAATVADLNLTGQRDRSRIEFAITILLLVILLIIYRNPITMVLPLITIGMSVVVAQRLVAIAGLAGLGIANQSIIFMSGMMVGAGTDYAVFLISRYHDYLRQGADSDQAVKKALTSIGKVIAASAATVAITFLGMVFTQLGILKTVGPMLGISVAVVFFAAVTLLPALMVLTGRRGWIAPRRDLTRRFWRSSGVHIVRRPKTHLLASALVLVILAGCAGLARYNYDDRKTLPASVESSIGYAALDKHFPSNLIIPEYLFIQSSTDLRTPKALADLEQMVQRVSQVPGVAMVRGITRPAGRSLEQARTSWQAGEVGSKLDEGSKQIAAHTGDIDKLAGGANLMASKLGDVRAQVNRAISTVGGLIDALAYLQDLLGGNRVLGELEGAEKLIGSMRALGDTIDADASFVANNTEWASPVLGALDSSPMCTADPACASARTELQRLVTARDDGTLAKISELARQLQATRAVQTLAATVSGLRGALATVIRAMGSLGMSSPGGVRSKINLVNKGVNDLADGSRQLAEGVQLLVDQVKKMGFGLGEASAFLLAMKDTATTPAMAGFYIPPELLSYATGESVKAETMPSEYRDLLGGLNVDQLKKVAAAFISPDGHSIRYLIQTDLNPFSTAAMDQIDAITAAARGAQPNTALADAKVSVVGLPVVLKDTRDYSDHDLRLIIAMTVCIVLLILIVLLRAIVAPLYLIGSVIVSYLAALGIGVIVFQFLLGQEMHWSIPGLTFVILVAVGADYNMLLISRLREEAVLGVRSGVIRTVASTGGVITAAGLIMAASMYGLVFASLGSVVQGAFVLGTGLLLDTFLVRTVTVPAIAVLVGQANWWLPSSWRPATWWPLGRRRGRAQRTKRKPLLPKEEEEQSPPDDDDLIGLWLHDGLRL