mftB Resolved · high auto-curated

H37Rv Rv0692 · MTBC0 mtbc0_000733 · 109 aa · 795917–796246 (+) · RefSeq NP_215206.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)mycofactocin system protein MftB
MTBC0 PGAP re-annotationmycofactocin biosynthesis chaperone MftB
Revised (this work)Mycofactocin biosynthesis chaperone MftB. Pfam: MftB_chaperone (PF26520.1).

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

Curated reference (UniProt)

UniProt P95038 SwissProt · reviewed · Inferred from homology
UniProt namePeptide chaperone MftB
Curated functionPeptide chaperone involved in the biosynthesis of the enzyme cofactor mycofactocin (MFT). Binds MftA and MftC with high affinity, and is essential for MftC activity on MftA, likely via the formation of a ternary complex.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionMycofactocin system
Orthologous groupCOG0535

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
MftB_chaperonePF26520.1 8.6e-3427–103 Peptide chaperone MftB family

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

Closest characterised functional partner: mftC (mycofactocin radical SAM maturase MftC), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0693 mftC mycofactocin radical SAM maturase MftC 999 1000 ctx neighborhood:882 cooccurence:774 coexpression:845 database:900 textmining:907
Rv0694 mftD mycofactocin system heme/flavin oxidoreductase MftD 999 990 ctx neighborhood:882 cooccurence:699 coexpression:734 textmining:907
Rv0695 mftE mycofactocin system creatinine amidohydrolase family protein MftE 998 967 ctx neighborhood:738 cooccurence:757 database:500 textmining:943
Rv0696 mftF mycofactocin biosynthesis glycosyltransferase MftF 994 931 ctx neighborhood:702 cooccurence:769 textmining:929
Rv0691c mftR mycofactocin biosynthesis transcriptional regulator MftR 980 902 ctx neighborhood:603 cooccurence:762 textmining:812
Rv0691A mftA mycofactocin precursor 984 882 ctx neighborhood:882 textmining:870
Rv1990A Rv1990A, len: 111 aa. Possible dehydrogenase (fragment), similar to N-terminal part of several dehydrogenases and hypothetical proteins, e.g 758 750 ctx cooccurence:748
Rv0697 mftG dehydrogenase 716 705 ctx neighborhood:702
Rv0690c hyp hypothetical protein 608 607 ctx neighborhood:595
Rv3169 hyp hypothetical protein 521 522 ctx cooccurence:520
Rv2425c hyp hypothetical protein 499 500 ctx cooccurence:464
Rv2750 dehydrogenase 815 496 ctx cooccurence:496 textmining:648
Rv0687 NAD-dependent oxidoreductase 792 439 ctx cooccurence:437 textmining:645
Rv1681 moeX molybdopterin biosynthesis protein MoeX 408 321
Rv0761c adhB alcohol dehydrogenase B 857 271 textmining:812

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: mycofactocin system protein MftB
  • MTBC0 PGAP product: mycofactocin biosynthesis chaperone MftB
  • Pfam (hmmscan --cut_ga): MftB_chaperone PF26520.1 (E=9e-34)
  • (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_215206.1)
  • Domains: Pfam-A via hmmscan --cut_ga — MftB_chaperone (PF26520.1)
  • 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 COG0535
  • Curated reference: UniProt P95038 (SwissProt, reviewed; Inferred from homology)
  • 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 — 16 functional partner(s); context anchor mftC
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_000733|Rv0692|mftB
MWGLLTVPAPAQARRADSSEFDPDRGWRLHPQVAVRPEPFGALLYHFGTRKLSFLKNRTILAVVQTLADYPDIRSACRGAGVDDCDQDPYLHALSVLAGSNMLVPRQTT