mltG Resolved · high auto-curated

H37Rv Rv2553c · MTBC0 mtbc0_002721 · 417 aa · 2895557–2896810 (-) · RefSeq NP_217069.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)membrane protein
MTBC0 PGAP re-annotationendolytic transglycosylase MltG
Revised (this work)Endolytic transglycosylase MltG. Pfam: YceG (PF02618.22).

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

Curated reference (UniProt)

UniProt I6XEK6 TrEMBL · unreviewed · Evidence at protein level
UniProt nameEndolytic murein transglycosylase
EC (curated) EC 4.2.2.29
Curated functionFunctions as a peptidoglycan terminase that cleaves nascent peptidoglycan strands endolytically to terminate their elongation.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namemltG
eggNOG descriptionFunctions as a peptidoglycan terminase that cleaves nascent peptidoglycan strands endolytically to terminate their elongation
Orthologous groupCOG1559
KEGG orthology K07082

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 1.054 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 3 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
YceGPF02618.22 3.4e-6586–405 YceG-like family

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

Closest characterised functional partner: aroE (shikimate 5-dehydrogenase), high confidence from genomic context alone (score 968 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2552c aroE shikimate 5-dehydrogenase 968 968 ctx neighborhood:881 coexpression:746
Rv2555c alaS alanine--tRNA ligase 939 940 ctx neighborhood:881 coexpression:514
Rv2554c ruvX Holliday junction resolvase 908 909 ctx neighborhood:882
Rv2551c hyp hypothetical protein 849 849 ctx neighborhood:800
Rv2556c hyp hypothetical protein 782 782 ctx neighborhood:779
Rv1797 eccE5 ESX-5 type VII secretion system protein EccE 778 778 coexpression:778
Rv3870 eccCa1 ESX-1 secretion system protein EccCa 776 777 coexpression:731
Rv2364c era GTPase Era 743 744 coexpression:735
Rv0819 mshD mycothiol acetyltransferase 735 736 coexpression:735
Rv2942 mmpL7 transmembrane transport protein MmpL7 747 735 coexpression:734
Rv3092c integral membrane protein 733 733 coexpression:733
Rv2851c GCN5-like N-acetyltransferase 731 732 coexpression:731
Rv3806c ubiA decaprenyl-phosphate phosphoribosyltransferase 731 731 coexpression:731
Rv3608c folP1 dihydropteroate synthase 790 662 coexpression:651 textmining:405
Rv3682 ponA2 bifunctional penicillin-insensitive transglycosylase/penicillin-sensitive transpeptidase 782 643 ctx cooccurence:577 textmining:416

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: membrane protein
  • MTBC0 PGAP product: endolytic transglycosylase MltG
  • Pfam (hmmscan --cut_ga): YceG PF02618.22 (E=3e-65)
  • (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_217069.1)
  • Domains: Pfam-A via hmmscan --cut_ga — YceG (PF02618.22)
  • 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 COG1559
  • Curated reference: UniProt I6XEK6 (TrEMBL, unreviewed; 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 — 49 functional partner(s); context anchor aroE
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002721|Rv2553c|mltG
MPDGGHRHRAQPVSVRPNRHRRTRVSRAQRRHAQQIRRRRRVAGGFALSLLVVVVVVAVVVGAKLWQTMLGFGNDYTGPGKRDIVIQIRAGDSTTAVGETLLKHGVVATVRAFVDAAHGNTAISSIQPGFYRMRTEISAASAVARLTDPHNRVGKLVIPEGRQLDDTTDMKTNVVNPGIFALISRATCVDLDGTQRCVSVADLRAAASRSTPTMLSVPRWAVGPVMELGTDHRRIEGLIAPGTFNIDPSASAETILATLISAGAVEYMKSGLVDTAKSLGLSPYDILVVASLVQQEANTQDFPKVARVIYNRLHEHRTLEFDSTVNYPLDRREVATSDTDRAQRTPWNTYMAQGLPATAICSPGVDALRAAEHPVPGDWLYFVTIDSQGTTLFTRDYQQHLANIELAKHNGVLDSAR