ponA2 Resolved · high auto-curated

H37Rv Rv3682 · MTBC0 - · 810 aa · 4121916–4124348 (+) · RefSeq YP_178005.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)bifunctional penicillin-insensitive transglycosylase/penicillin-sensitive transpeptidase
MTBC0 PGAP re-annotation
Revised (this work)Bifunctional penicillin-insensitive transglycosylase/penicillin-sensitive transpeptidase. Pfam: Transgly (PF00912.29), Transpeptidase (PF00905.28), PASTA (PF03793.25).

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

Annotated on the H37Rv protein: this gene has no 1:1 ancestral MTBC0 anchor (PE/PPE, paralogue, IS element, or otherwise unanchored CDS).

Curated reference (UniProt)

UniProt I6YGX2 SwissProt · reviewed · Evidence at protein level
UniProt namePenicillin-binding protein A2
EC (curated) EC 2.4.99.28, EC 3.4.16.4
Curated functionCell wall formation. Synthesis of cross-linked peptidoglycan from the lipid intermediates. The enzyme has a penicillin-insensitive transglycosylase N-terminal domain (formation of linear glycan strands) and a penicillin-sensitive transpeptidase C-terminal domain (cross-linking of the peptide subunits).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category M Cell wall / membrane / envelope biogenesis
Preferred namepon1
eggNOG descriptionpenicillin-binding protein
Orthologous groupCOG0744

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 0.344 · purifying
Polymorphic sites (≥ 0.1% of strains) 15 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
TransglyPF00912.29 2.3e-5370–256 Transglycosylase
TranspeptidasePF00905.28 1.7e-17364–619 Penicillin binding protein transpeptidase domain
PASTAPF03793.25 7.9e-12702–762 PASTA domain

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

Closest characterised functional partner: rodA (cell division protein RodA), high confidence from genomic context alone (score 817 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2927c sepIVA hyp hypothetical protein 944 922 experimental:848
Rv2145c wag31 cell wall synthesis protein Wag31 937 913 experimental:848
Rv1209 hyp hypothetical protein 930 906 experimental:807
Rv0017c rodA cell division protein RodA 869 817 ctx cooccurence:551 database:500
Rv0016c pbpA penicillin-binding protein PbpA 927 805 ctx cooccurence:634 experimental:419 textmining:644
Rv2163c pbpB penicillin-binding membrane protein PbpB 889 787 ctx cooccurence:601 experimental:419 textmining:504
Rv2864c penicillin-binding lipoprotein 941 785 ctx cooccurence:599 experimental:419 textmining:738
Rv1650 pheT phenylalanine--tRNA ligase subunit beta 745 745 ctx neighborhood:525 coexpression:403
Rv2154c ftsW lipid II flippase FtsW 792 709 ctx cooccurence:629
Rv0358 hyp hypothetical protein 685 686 ctx cooccurence:685
Rv1638A hyp hypothetical protein 687 667 ctx cooccurence:485
Rv0050 ponA1 bifunctional penicillin-insensitive transglycosylase/penicillin-sensitive transpeptidase 835 660 database:500 textmining:536
Rv3205c hyp hypothetical protein 647 648 ctx cooccurence:632
Rv2446c integral membrane protein 647 647 ctx cooccurence:643
Rv0556 transmembrane protein 645 645 ctx cooccurence:630

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

  • Annotation from H37Rv (no MTBC0 1:1 anchor; H37Rv protein used): bifunctional penicillin-insensitive transglycosylase/penicillin-sensitive transpeptidase
  • Pfam (hmmscan --cut_ga): Transgly PF00912.29 (E=2e-53), Transpeptidase PF00905.28 (E=2e-17), PASTA PF03793.25 (E=8e-12)
  • (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 YP_178005.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Transgly (PF00912.29), Transpeptidase (PF00905.28), PASTA (PF03793.25)
  • 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 COG0744
  • Curated reference: UniProt I6YGX2 (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 — 114 functional partner(s); context anchor rodA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv3682|ponA2
MPERLPAAITVLKLAGCCLLASVVATALTFPFAGGLGLMSNRASEVVANGSAQLLEGQVPAVSTMVDAKGNTIAWLYSQRRFEVPSDKIANTMKLAIVSIEDKRFADHSGVDWKGTLTGLAGYASGDLDTRGGSTLEQQYVKNYQLLVTAQTDAEKRAAVETTPARKLREIRMALTLDKTFTKSEILTRYLNLVSFGNNSFGVQDAAQTYFGINASDLNWQQAALLAGMVQSTSTLNPYTNPDGALARRNVVLDTMIENLPGEAEALRAAKAEPLGVLPQPNELPRGCIAAGDRAFFCDYVQEYLSRAGISKEQVATGGYLIRTTLDPEVQAPVKAAIDKYASPNLAGISSVMSVIKPGKDAHKVLAMASNRKYGLDLEAGETMRPQPFSLVGDGAGSIFKIFTTAAALDMGMGINAQLDVPPRFQAKGLGSGGAKGCPKETWCVVNAGNYRGSMNVTDALATSPNTAFAKLISQVGVGRAVDMAIKLGLRSYANPGTARDYNPDSNESLADFVKRQNLGSFTLGPIELNALELSNVAATLASGGVWCPPNPIDQLIDRNGNEVAVTTETCDQVVPAGLANTLANAMSKDAVGSGTAAGSAGAAGWDLPMSGKTGTTEAHRSAGFVGFTNRYAAANYIYDDSSSPTDLCSGPLRHCGSGDLYGGNEPSRTWFAAMKPIANNFGEVQLPPTDPRYVDGAPGSRVPSVAGLDVDAARQRLKDAGFQVADQTNSVNSSAKYGEVVGTSPSGQTIPGSIVTIQISNGIPPAPPPPPLPEDGGPPPPVGSQVVEIPGLPPITIPLLAPPPPAPPP