cysM Resolved · high auto-curated

H37Rv Rv1336 · MTBC0 mtbc0_001433 · 323 aa · 1514096–1515067 (+) · RefSeq NP_215852.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)O-phosphoserine sulfhydrylase
MTBC0 PGAP re-annotationO-phosphoserine sulfhydrylase
Revised (this work)O-phosphoserine sulfhydrylase. Pfam: PALP (PF00291.32).

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

Curated reference (UniProt)

UniProt P9WP53 SwissProt · reviewed · Evidence at protein level
UniProt nameO-phosphoserine sulfhydrylase
EC (curated) EC 2.5.1.113
Curated functionCatalyzes the formation of a covalent CysO-cysteine adduct via a sulfur transfer, using the thiocarboxylated sulfur carrier protein CysO-COSH as sulfur donor and O-phospho-L-serine (OPS) as sulfur acceptor. Can also use sodium sulfide as sulfur donor in vitro, albeit with less efficiency, but not thiosulfate or thio-nitro-benzoate. O-acetylserine (OAS) is a very poor substrate in comparison with OPS. May be of particular importance for cysteine biosynthesis in the persistent phase of M.tuberculosis.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category E Amino acid transport and metabolism
Preferred namecysM
eggNOG descriptioncysteine
Orthologous groupCOG0031
EC number EC 2.5.1.113
KEGG orthology K21148
KEGG pathways map04122
Gene Ontology (59) GO:0000096, GO:0000097, GO:0003674, GO:0003824, GO:0005488, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0006082, GO:0006520 +47 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 1.44 · diversifying/relaxed
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 2 missense, 2 nonsense, 2 frameshift
Disruption 4 distinct premature-stop/frameshift site(s); most common in 0.77% of strains (1121) · convergent

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
PALPPF00291.32 9.2e-678–293 Pyridoxal-phosphate dependent enzyme

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

Closest characterised functional partner: cysO (sulfur carrier protein CysO), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1335 cysO sulfur carrier protein CysO 999 1000 ctx neighborhood:876 coexpression:808 experimental:999 textmining:901
Rv1334 mec [CysO 991 992 ctx neighborhood:847 cooccurence:439 coexpression:809 database:500
Rv1338 murI glutamate racemase 979 973 ctx neighborhood:881 coexpression:785
Rv1337 integral membrane protein 960 905 ctx neighborhood:881 textmining:594
Rv1332 transcriptional regulator 875 855 ctx neighborhood:829
Rv1333 hydrolase 854 854 ctx neighborhood:847
Rv1339 hyp hypothetical protein 844 845 ctx neighborhood:843
Rv1340 rphA ribonuclease PH 835 835 ctx neighborhood:825
Rv1331 clpS ATP-dependent Clp protease adapter protein ClpS 837 830 ctx neighborhood:829
Rv1341 rdgB non-canonical purine NTP pyrophosphatase 813 813 ctx neighborhood:780
Rv2335 cysE serine acetyltransferase 947 795 coexpression:495 textmining:753
Rv1286 cysC adenylyl-sulfate kinase 909 784 coexpression:755 textmining:600
Rv1330c pncB1 nicotinic acid phosphoribosyltransferase PncB1 749 749 ctx neighborhood:747
Rv1329c dinG ATP-dependent helicase DinG 725 725 ctx neighborhood:719
Rv3206c moeB1 adenylyltransferase/sulfurtransferase MoeZ 927 617 database:500 textmining:820

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: O-phosphoserine sulfhydrylase
  • MTBC0 PGAP product: O-phosphoserine sulfhydrylase
  • Pfam (hmmscan --cut_ga): PALP PF00291.32 (E=9e-67)
  • (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_215852.1)
  • Domains: Pfam-A via hmmscan --cut_ga — PALP (PF00291.32)
  • 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 COG0031
  • Curated reference: UniProt P9WP53 (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 — 48 functional partner(s); context anchor cysO
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001433|Rv1336|cysM
MTRYDSLLQALGNTPLVGLQRLSPRWDDGRDGPHVRLWAKLEDRNPTGSIKDRPAVRMIEQAEADGLLRPGATILEPTSGNTGISLAMAARLKGYRLICVMPENTSVERRQLLELYGAQIIFSAAEGGSNTAVATAKELAATNPSWVMLYQYGNPANTDSHYCGTGPELLADLPEITHFVAGLGTTGTLMGTGRFLREHVANVKIVAAEPRYGEGVYALRNMDEGFVPELYDPEILTARYSVGAVDAVRRTRELVHTEGIFAGISTGAVLHAALGVGAGALAAGERADIALVVADAGWKYLSTGAYAGSLDDAETALEGQLWA