ispD Resolved · high auto-curated

H37Rv Rv3582c · MTBC0 mtbc0_003801 · 231 aa · 4048021–4048716 (-) · RefSeq NP_218099.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase
MTBC0 PGAP re-annotation2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase
Revised (this work)2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase. Pfam: IspD (PF01128.26), CTP_transf_3 (PF02348.26), NTP_transf_3 (PF12804.14).

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

Curated reference (UniProt)

UniProt P9WKG9 SwissProt · reviewed · Evidence at protein level
UniProt name2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase
EC (curated) EC 2.7.7.60
Curated functionCatalyzes the formation of 4-diphosphocytidyl-2-C-methyl-D-erythritol from CTP and 2-C-methyl-D-erythritol 4-phosphate (MEP).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category I Lipid transport and metabolism
Preferred nameispD
eggNOG descriptionCatalyzes the formation of 4-diphosphocytidyl-2-C- methyl-D-erythritol from CTP and 2-C-methyl-D-erythritol 4- phosphate (MEP)
Orthologous groupCOG1211
EC number EC 2.7.7.60
KEGG orthology K00991
KEGG pathways map00900, map01100, map01110, map01130
KEGG modules M00096
Gene Ontology (73) GO:0000166, GO:0000287, GO:0001882, GO:0001884, GO:0002135, GO:0003674, GO:0003824, GO:0005488, GO:0005575, GO:0005623, GO:0005886, GO:0006081 +61 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 0.264 · purifying
Polymorphic sites (≥ 0.1% of strains) 3 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
IspDPF01128.26 2.1e-868–230 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase
CTP_transf_3PF02348.26 5.3e-069–150 Cytidylyltransferase
NTP_transf_3PF12804.14 1.8e-0910–135 MobA-like NTP transferase domain

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

Closest characterised functional partner: ispF (2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3581c ispF 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase 999 1000 ctx neighborhood:882 fusion:900 cooccurence:770 coexpression:949 textmining:965
Rv2870c dxr 1-deoxy-D-xylulose 5-phosphate reductoisomerase 998 977 ctx cooccurence:762 database:900 textmining:957
Rv1011 ispE 4-diphosphocytidyl-2C-methyl-D-erythritol kinase 998 974 ctx cooccurence:730 database:900 textmining:949
Rv3583c carD RNA polymerase-binding transcription factor CarD 955 887 ctx neighborhood:865 textmining:622
Rv3579c rlmB 23S rRNA (guanosine(2251)-2'-O)-methyltransferase RlmB 800 800 ctx neighborhood:799
Rv3580c cysS1 cysteine--tRNA ligase 800 800 ctx neighborhood:799
Rv2868c gcpE 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase (flavodoxin) 986 762 ctx cooccurence:751 textmining:948
Rv1110 lytB2 4-hydroxy-3-methylbut-2-enyl diphosphate reductase 910 761 ctx cooccurence:750 textmining:642
Rv3382c lytB1 4-hydroxy-3-methylbut-2-enyl diphosphate reductase 945 759 ctx cooccurence:749 textmining:785
Rv3586 disA DNA integrity scanning protein DisA 691 692 ctx neighborhood:491 coexpression:419
Rv3585 radA DNA repair protein RadA 710 665 ctx neighborhood:453 coexpression:412
Rv2682c dxs1 1-deoxy-D-xylulose 5-phosphate synthase 969 659 ctx cooccurence:619 textmining:915
Rv3379c dxs2 1-deoxy-D-xylulose-5-phosphate synthase 799 618 ctx cooccurence:577 textmining:496
Rv3584 lpqE lipoprotein LpqE 450 451 ctx neighborhood:448
Rv2881c cdsA phosphatidate cytidylyltransferase 430 224

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: 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase
  • MTBC0 PGAP product: 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase
  • Pfam (hmmscan --cut_ga): IspD PF01128.26 (E=2e-86), CTP_transf_3 PF02348.26 (E=5e-06), NTP_transf_3 PF12804.14 (E=2e-09)
  • (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_218099.1)
  • Domains: Pfam-A via hmmscan --cut_ga — IspD (PF01128.26), CTP_transf_3 (PF02348.26), NTP_transf_3 (PF12804.14)
  • 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 COG1211
  • Curated reference: UniProt P9WKG9 (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 — 26 functional partner(s); context anchor ispF
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003801|Rv3582c|ispD
MVREAGEVVAIVPAAGSGERLAVGVPKAFYQLDGQTLIERAVDGLLDSGVVDTVVVAVPADRTDEARQILGHRAMIVAGGSNRTDTVNLALTVLSGTAEPEFVLVHDAARALTPPALVARVVEALRDGYAAVVPVLPLSDTIKAVDANGVVLGTPERAGLRAVQTPQGFTTDLLLRSYQRGSLDLPAAEYTDDASLVEHIGGQVQVVDGDPLAFKITTKLDLLLAQAIVRG