obg Resolved · high auto-curated
H37Rv Rv2440c · MTBC0 mtbc0_002599 ·
479 aa · 2762495–2763934 (-) ·
RefSeq NP_216956.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | GTPase Obg |
|---|---|
| MTBC0 PGAP re-annotation | GTPase ObgE |
| Revised (this work) | GTPase ObgE. Pfam: GTP1_OBG (PF01018.29), MMR_HSR1 (PF01926.30), FeoB_N (PF02421.25), DUF1967 (PF09269.17). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WMT1
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | GTPase Obg |
| EC (curated) |
EC 3.6.5.-
|
| Curated function | An essential GTPase which binds GTP, GDP and possibly (p)ppGpp with moderate affinity, with high nucleotide exchange rates and a fairly low GTP hydrolysis rate. Plays a role in control of the cell cycle, stress response, ribosome biogenesis and in those bacteria that undergo differentiation, in morphogenesis control (By similarity). GTPase activity is not inhibited by ATP or GDP. Overexpression decreases cell growth starting in late log phase and continuing into stationary phase. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
S Function unknown
|
|---|---|
| Preferred name | obg |
| eggNOG description | An essential GTPase which binds GTP, GDP and possibly (p)ppGpp with moderate affinity, with high nucleotide exchange rates and a fairly low GTP hydrolysis rate. Plays a role in control of the cell cycle, stress response, ribosome biogenesis and in those bacteria that undergo differentiation, in morphogenesis control |
| Orthologous group | COG0536 |
| KEGG orthology |
K03979
|
| Gene Ontology (51) |
GO:0000287, GO:0003674, GO:0003824, GO:0003924, GO:0005488, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005840, GO:0005886, GO:0006464 +39 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 | 0.439 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 5 synonymous, 6 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)
| Pfam | Accession | i-Evalue | Residues | Description |
|---|---|---|---|---|
GTP1_OBG | PF01018.29 | 2.4e-52 | 5–158 | GTP1/OBG |
MMR_HSR1 | PF01926.30 | 2.5e-21 | 161–255 | 50S ribosome-binding GTPase |
FeoB_N | PF02421.25 | 5.7e-07 | 162–248 | Ferrous iron transport protein B |
DUF1967 | PF09269.17 | 4.0e-24 | 366–434 | Domain of unknown function (DUF1967) |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: rpmA (50S ribosomal protein L27), high confidence from genomic context alone (score 970 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv2441c rpmA |
50S ribosomal protein L27 | 996 | 970 ctx | neighborhood:636 coexpression:405 experimental:843 textmining:887 |
Rv1643 rplT |
50S ribosomal protein L20 | 962 | 957 ctx | cooccurence:531 coexpression:448 experimental:843 |
Rv2442c rplU |
50S ribosomal protein L21 | 971 | 953 ctx | neighborhood:622 experimental:843 textmining:418 |
Rv2420c rsfS hyp |
hypothetical protein | 931 | 911 | experimental:885 |
Rv2904c rplS |
50S ribosomal protein L19 | 914 | 909 | experimental:841 |
Rv2439c proB |
glutamate 5-kinase protein | 988 | 904 ctx | neighborhood:881 textmining:889 |
Rv0640 rplK |
50S ribosomal protein L11 | 908 | 893 | experimental:878 |
Rv3443c rplM |
50S ribosomal protein L13 | 884 | 877 | experimental:826 |
Rv0723 rplO |
50S ribosomal protein L15 | 876 | 876 | experimental:805 |
Rv0701 rplC |
50S ribosomal protein L3 | 874 | 875 | experimental:822 |
Rv0715 rplX |
50S ribosomal protein L24 | 882 | 870 | experimental:822 |
Rv0056 rplI |
50S ribosomal protein L9 | 882 | 869 | experimental:843 |
Rv0702 rplD |
50S ribosomal protein L4 | 869 | 869 | experimental:822 |
Rv3456c rplQ |
50S ribosomal protein L17 | 884 | 865 | experimental:844 |
Rv0706 rplV |
50S ribosomal protein L22 | 863 | 858 | experimental:822 |
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: GTPase Obg
- MTBC0 PGAP product: GTPase ObgE
- Pfam (hmmscan --cut_ga): GTP1_OBG PF01018.29 (E=2e-52), MMR_HSR1 PF01926.30 (E=2e-21), FeoB_N PF02421.25 (E=6e-07), DUF1967 PF09269.17 (E=4e-24)
- (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_216956.1)
- Domains: Pfam-A via hmmscan --cut_ga — GTP1_OBG (PF01018.29), MMR_HSR1 (PF01926.30), FeoB_N (PF02421.25), DUF1967 (PF09269.17)
- 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
COG0536 - Curated reference: UniProt P9WMT1 (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 —
138 functional partner(s); context anchor
rpmA - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_002599|Rv2440c|obg MPRFVDRVVIHTRAGSGGNGCASVHREKFKPLGGPDGGNGGRGGSIVFVVDPQVHTLLDFHFRPHLTAASGKHGMGNNRDGAAGADLEVKVPEGTVVLDENGRLLADLVGAGTRFEAAAGGRGGLGNAALASRVRKAPGFALLGEKGQSRDLTLELKTVADVGLVGFPSAGKSSLVSAISAAKPKIADYPFTTLVPNLGVVSAGEHAFTVADVPGLIPGASRGRGLGLDFLRHIERCAVLVHVVDCATAEPGRDPISDIDALETELACYTPTLQGDAALGDLAARPRAVVLNKIDVPEARELAEFVRDDIAQRGWPVFCVSTATRENLQPLIFGLSQMISDYNAARPVAVPRRPVIRPIPVDDSGFTVEPDGHGGFVVSGARPERWIDQTNFDNDEAVGYLADRLARLGVEEELLRLGARSGCAVTIGEMTFDWEPQTPAGEPVAMSGRGTDPRLDSNKRVGAAERKAARSRRREHGDG