KpATCC43816 Protein target profile

threonine--tRNA ligase

Accession: VK055_0276

Gene: AIK78902.1 thrS 3D evidence: AlphaFold DB model + ColabFold model Metabolism 3 reactions UniProt A0A0H3GPK3
Length 622
Pocket druggability (P2Rank · AlphaFold DB model) 0.858
Metabolic reactions 3
Chokepoint Yes
Direct ligand evidence 0 90 total records
Functional annotation 0 EC 8 GO
Target summary

Promising target candidate with multiple supporting evidence streams.

Automated synthesis of the evidence currently loaded. Review the underlying records before prioritizing this protein.

Terms and data sources used on this page

PDB: experimentally determined structures from the Protein Data Bank. These are the strongest structural evidence, but may cover only part of the protein.

AlphaFold DB model: a precomputed predicted structure downloaded from AlphaFold Database/UniProt, not an experiment performed here.

ColabFold model: a predicted structure generated for this workspace; interpret it with coverage and confidence.

pLDDT: confidence score for predicted structures. High values support local geometry; low values mean the region should not drive pocket interpretation.

FPocket / P2Rank: software tools that predict possible ligand-binding pockets on a 3D structure. They are useful screening signals, not experimental validation.

Druggability: a pocket-based estimate of whether a small molecule could bind productively. It does not mean a drug already exists.

PDB ligand: a compound observed in an experimental structure. Direct same-protein records are stronger than homolog-transferred records.

ChEMBL: a public database of measured compound bioactivity. Direct entries are stronger than entries transferred from similar proteins.

ZINC: a purchasable-compound database. Here it marks proposed candidates from chemical similarity, not measured binders.

LigQ / LigQ_2: an internal Target pipeline step that gathers PDB, ChEMBL, and ZINC ligand evidence for each protein.

Off-target: sequence similarity to proteins we prefer not to hit, such as human proteins or beneficial gut microbiome proteins.

DEG: Database of Essential Genes. A match suggests the protein resembles genes known to be essential in other organisms.

Roary / CoreCruncher: pan-genome tools used to decide whether a gene is core across analyzed strains or accessory/strain-specific.

EC / GO: functional annotations: EC describes enzyme reactions; GO describes biological process, molecular function, or cellular component.

KEGG pathway: a curated metabolic route label used here to group reactions imported from the metabolic model.

Chokepoint: a metabolic reaction that is the only producer or consumer of a metabolite in the imported model.

Prioritization evidence

Selectivity, essentiality, structural confidence, conservation, and predicted binding-site evidence.

Off-target risk

Human off-target
Hit
Human identity (%)
40.336 Lower values reduce human off-target concern.
Human E-value
4.32e-88
Gut microbiome similarity
6.4% of screened genomes Lower prevalence suggests narrower overlap with the screened gut microbiome.

Essentiality

Essential (DEG)
Y
DEG identity (%)
96.302 Higher values support similarity to known essential genes.
DEG E-value
0.0 Smaller values mean stronger essential-gene similarity.

Structure confidence

ColabFold pLDDT
96.14 0-100 confidence; >70 supports local structural interpretation.

Binding-site evidence

AlphaFold DB / UniProt model

P2Rank's binding-site probability is the primary druggability signal shown across the app; FPocket's druggability score is shown alongside it for comparison. Both estimate small-molecule pocket quality after applying the curated structure priority — neither is experimental binding evidence. The 3D viewer may show a different loaded structure, so visible pockets can differ.

Druggability (P2Rank) 0.858
Structure A0A0H3GPK3
Pocket Pocket 1
Druggability (FPocket) 0.204
Structure A0A0H3GPK3
Pocket Pocket 2
ColabFold model
P2Rank 0.888 · Pocket 1
FPocket 0.268 · Pocket 2
Core conservation Conserved core gene
Roary core
CoreCruncher core
Gut microbiome 303 / 4744 genomes with a hit
Prevalence 6.4%

Metabolic context

Reactions catalyzed, pathway membership, and centrality in the genome-scale metabolic network.

Explore metabolic network

Attractive metabolic target: catalyzes a producing chokepoint reaction in Aminoacyl-tRNA biosynthesis.

Relative network centrality 0.0% more central than 0.0% of genes in this genome
Chokepoint Chokepoint gene
Catalyzed reactions

3 reactions mapped to this gene in the metabolic model. Open the full network to see each one, with substrates/products and the reaction-reaction map.

Imported from KpATCC43816.sbml · 2026-07-09

Sequence

Primary amino-acid sequence viewer.

MDVALDIGPGLAKATIAGRVNGELVDACDPIESDSTLSIITAKDEEGLEIIRHSCAHLLGHAIKQLWPNTKMAIGPVVDNGFYYDVDLDHTLTQEDIDALEKRMHELAEKNYDVIKKKVSWHEARETFVKRGESYKVSILDENIAHDDKPGLYHHEEYIDMCRGPHVPNMRFCHHFKLMKTAGAYWRGDSNNKMLQRIYGTAWADKKALNAYLQRLEEAAKRDHRKIGKQLDLYHMQEEAPGMVFWHNDGWTIFRELETFVRSKLKEYQYQEVKGPFMMDRVLWEKTGHWDNYKDAMFTTSSENREYCIKPMNCPGHVQIFNQGLKSYRDLPLRMAEFGSCHRNEPSGALHGLMRVRGFTQDDAHIFCTEDQVRDEVNACIRMVYDMYSTFGFEKIVVKLSTRPEKRIGSDETWDRAEADLAVALEENNIPFEYQLGEGAFYGPKIEFTLYDCLDRAWQCGTVQLDFSLPQRLSASYVGENNERQVPVMIHRAILGSLERFIGILTEEFAGFFPTWIAPVQVVVMNITDSQAEYVNELTRKLQNAGIRVKADLRNEKIGFKIREHTLRRVPYMLVCGDKEVEAGKVAVRTRRGKDLGSMDVNEVIEKLQQEIRSRSLQQLEE

Functional annotations

Enzyme classification and Gene Ontology terms linked to this protein.

8 GO

Subcellular localization

Localization
Cytoplasmic

Gene Ontology (GO)

8
  • GO:0005524 Binding to ATP, adenosine 5'-triphosphate, a universally important coenzyme and enzyme regulator.
  • GO:0043039 The chemical reactions and pathways by which the various amino acids become bonded to their corresponding tRNAs. The most common route for synthesis of aminoacyl tRNA is by the formation of an ester bond between the 3'-hydroxyl group of the most 3' adenosine of the tRNA and the alpha carboxylic acid group of an amino acid, usually catalyzed by the cognate aminoacyl-tRNA ligase. A given aminoacyl-tRNA ligase aminoacylates all species of an isoaccepting group of tRNA molecules.
  • GO:0004829 Catalysis of the reaction: ATP + L-threonine + tRNA(Thr) = AMP + diphosphate + L-threonyl-tRNA(Thr).
  • GO:0006435 The process of coupling threonine to threonyl-tRNA, catalyzed by threonyl-tRNA synthetase. The threonyl-tRNA synthetase is a class-II synthetase. The activated amino acid is transferred to the 3'-OH group of a threonine-accetping tRNA.
  • GO:0004812 Catalysis of the formation of aminoacyl-tRNA from ATP, amino acid, and tRNA with the release of diphosphate and AMP.
  • GO:0000166 Binding to a nucleotide, any compound consisting of a nucleoside that is esterified with (ortho)phosphate or an oligophosphate at any hydroxyl group on the ribose or deoxyribose.
  • GO:0006418 The synthesis of aminoacyl tRNA by the formation of an ester bond between the 3'-hydroxyl group of the most 3' adenosine of the tRNA and the alpha carboxylic acid group of an amino acid, to be used in ribosome-mediated polypeptide synthesis.
  • GO:0005737 The contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.

Sequence domains and features

Domain and signature matches imported from InterPro and related databases.

53 records
Show feature table
Start End DB Term Name
1 41 Pfam PF02824 TGS domain
1 41 InterPro IPR004095 TGS
48 202 Gene3D G3DSA:3.30.980.10 -
512 619 FunFam G3DSA:3.40.50.800:FF:000001 Threonine--tRNA ligase
46 614 Hamap MF_00184 Threonine--tRNA ligase [thrS].
46 614 InterPro IPR002320 Threonine-tRNA ligase, class IIa
223 514 ProSiteProfiles PS50862 Aminoacyl-transfer RNA synthetases class-II family profile.
223 514 InterPro IPR006195 Aminoacyl-tRNA synthetase, class II
1 44 Gene3D G3DSA:3.10.20.30 -
1 44 InterPro IPR012675 Beta-grasp domain superfamily
1 41 ProSiteProfiles PS51880 TGS domain profile.
52 611 NCBIfam TIGR00418 threonine--tRNA ligase
52 611 InterPro IPR002320 Threonine-tRNA ligase, class IIa
444 472 PRINTS PR01047 Threonyl-tRNA synthetase signature
444 472 InterPro IPR002320 Threonine-tRNA ligase, class IIa
309 337 PRINTS PR01047 Threonyl-tRNA synthetase signature
309 337 InterPro IPR002320 Threonine-tRNA ligase, class IIa
342 365 PRINTS PR01047 Threonyl-tRNA synthetase signature
342 365 InterPro IPR002320 Threonine-tRNA ligase, class IIa
487 500 PRINTS PR01047 Threonyl-tRNA synthetase signature
487 500 InterPro IPR002320 Threonine-tRNA ligase, class IIa
514 526 PRINTS PR01047 Threonyl-tRNA synthetase signature
514 526 InterPro IPR002320 Threonine-tRNA ligase, class IIa
510 616 SUPERFAMILY SSF52954 Class II aaRS ABD-related
2 615 PANTHER PTHR11451 THREONINE-TRNA LIGASE
110 167 FunFam G3DSA:3.30.54.20:FF:000002 Threonine--tRNA ligase
222 519 CDD cd00771 ThrRS_core
222 519 InterPro IPR033728 Threonine-tRNA ligase catalytic core domain
1 41 SUPERFAMILY SSF81271 TGS-like
1 41 InterPro IPR012676 TGS-like
45 203 FunFam G3DSA:3.30.980.10:FF:000005 Threonyl-tRNA synthetase, mitochondrial
90 110 Coils Coil Coil
205 512 FunFam G3DSA:3.30.930.10:FF:000002 Threonine--tRNA ligase
152 199 Pfam PF07973 Threonyl and Alanyl tRNA synthetase second additional domain
152 199 InterPro IPR012947 Threonyl/alanyl tRNA synthetase, SAD
298 508 Pfam PF00587 tRNA synthetase class II core domain (G, H, P, S and T)
298 508 InterPro IPR002314 Aminoacyl-tRNA synthetase, class II (G/ P/ S/T)
43 221 SUPERFAMILY SSF55186 ThrRS/AlaRS common domain
43 221 InterPro IPR018163 Threonyl/alanyl tRNA synthetase, class II-like, putative editing domain superfamily
519 609 CDD cd00860 ThrRS_anticodon
519 609 InterPro IPR047246 Threonine-tRNA ligase, class IIa, anticodon-binding domain
223 505 SUPERFAMILY SSF55681 Class II aaRS and biotin synthetases
223 505 InterPro IPR045864 Class II Aminoacyl-tRNA synthetase/Biotinyl protein ligase (BPL) and lipoyl protein ligase (LPL)
512 622 Gene3D G3DSA:3.40.50.800 -
512 622 InterPro IPR036621 Anticodon-binding domain superfamily
150 199 SMART SM00863 tRNA_SAD_4
150 199 InterPro IPR012947 Threonyl/alanyl tRNA synthetase, SAD
521 610 Pfam PF03129 Anticodon binding domain
521 610 InterPro IPR004154 Anticodon-binding
203 511 Gene3D G3DSA:3.30.930.10 Bira Bifunctional Protein; Domain 2
203 511 InterPro IPR045864 Class II Aminoacyl-tRNA synthetase/Biotinyl protein ligase (BPL) and lipoyl protein ligase (LPL)
1 46 CDD cd01667 TGS_ThrRS
110 167 Gene3D G3DSA:3.30.54.20 -

3D structure

Selected loaded structure. Experimental PDB entries may cover only a portion of the sequence; AlphaFold DB and ColabFold models typically cover the full protein but remain computational predictions.

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Pocket score High Medium Low
How colors and pocket overlays are used
Uniform protein color marks the displayed model as a single molecular object.
Experimental PDB structures may be colored by chain to distinguish subunits or copies present in the file.
Pocket colors and alpha spheres are evidence overlays for predicted binding cavities; they are not alternative protein chains.
'Alpha spheres' is FPocket's own cavity-shape geometry, imported when available and aligned with the loaded structure.
'Pocket atoms'/'Predicted site atoms' show the pocket's residue atoms instead: P2Rank reports residues rather than alpha spheres, and FPocket falls back to this when alpha-sphere geometry is unavailable or doesn't align.
'No pocket geometry' means neither alpha spheres nor residue-position data could be found for that pocket; the layer just highlights the same residues as 'Nearby residues'.
Pocket details Inspect a specific pocket, or open the full viewer

Binding pockets · P2Rank

Druggability (P2Rank): high ≥ 0.5 · medium 0.2–0.49 · low < 0.2

Pocket 1 P2Rank #1
0.858
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Surrounding area
Pocket 2 P2Rank #2
0.459
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Surrounding area
Pocket 3 P2Rank #3
0.166
Show in viewer
Surrounding area
Pocket 4 P2Rank #4
0.054
Likely same site as FPocket 2 1.1 Å 7 shared residues 100% of smaller site
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Surrounding area
Pocket 5 P2Rank #5
0.027
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Surrounding area

Binding pockets · FPocket

Druggability (FPocket): high ≥ 0.7 · medium 0.4–0.69 · low < 0.4

Pocket 1 FPocket #2
0.204
Likely same site as P2Rank 4 1.1 Å 7 shared residues 100% of smaller site
Show in viewer
Surrounding area
Residue sets
UniProt: Binding site:334-334
UniProt: Binding site:385-385
UniProt: Binding site:511-511
All structural evidence 0 experimental · 2 predicted

Structural evidence

0 + 2

Experimental PDB entries plus predicted AlphaFold DB or ColabFold models. Click Switch to display a different loaded structure in the viewer.

Entry Method Resolution Chain Coverage Links Status
AlphaFold DB AF_A0A0H3GPK3
AlphaFold DB full sequence Viewing
ColabFold VK055_0276
ColabFold full sequence Loaded

Ligand evidence

Ligands grouped by evidence source. PDB ligands keep the source crystal visible, and loaded crystals can be opened directly in the structure viewer.

90 records
Chemistry signal

Structural and bioactivity evidence are both available for this target.

Direct evidence 0 same-protein records
Transferred evidence 40 records from similar proteins
Structural ligands 12 0 loaded crystals
Measured bioactivity 28 direct and transferred ChEMBL records
Proposed compounds 50 similarity-based ZINC candidates
Best available ligand signal
1B3 PDB via homolog 435.9 Da · LogP 1.05 · TPSA 161.3 Open detail RCSB PDB
2CR PDB via homolog Detail RCSB PDB
409 PDB via homolog Detail RCSB PDB
A3S PDB via homolog Detail RCSB PDB
BC9 PDB via homolog Detail RCSB PDB

Structural evidence inferred from similar proteins. The source crystal indicates where the ligand was observed; the UniProt column identifies the homologous protein carrying that ligand.

Show only:
Ligand Source crystal UniProt (homolog) MW · LogP · TPSA Lipinski PAINS SMILES
1B3 RCSB PDB P0A8M3 435.9 Da LogP 1.05 TPSA 161.3 ✓ Ro5 ✓ Clean C[C@H]([C@@H](C(=O)NS(=O)(=O)c1cccc(c1)c2ccc3c(…
2CR RCSB PDB P0A8M3 489.7 Da LogP 4.64 TPSA 127.9 ✓ Ro5 ✓ Clean CC1CC(CC(C(C(=CC=CCC(OC(=O)CC(C(C1)C)O)C2CCCC2C…
409 RCSB PDB P0A8M3 401.4 Da LogP 0.39 TPSA 161.3 ✓ Ro5 ✓ Clean C[C@H]([C@@H](C(=O)NS(=O)(=O)c1cccc(c1)c2ccc3c(…
A3S RCSB PDB P0A8M3 353.3 Da LogP -3.54 TPSA 194.7 2 viol. ✓ Clean c1nc(c2c(n1)n(cn2)[C@H]3[C@@H]([C@@H]([C@H](O3)…
BC9 RCSB PDB P26639 477.6 Da LogP 4.47 TPSA 127.9 ✓ Ro5 ✓ Clean CC1CC(CC(C(C(=CCCCC(OC(=O)CC(C(C1)C)O)C2CCC2C(=…
E4O RCSB PDB V7II86 385.3 Da LogP 1.08 TPSA 110.2 ✓ Ro5 ✓ Clean C[C@H]([C@@H](C(=O)NC/C=C/CN1C=Nc2cc(c(cc2C1=O)…
FQL RCSB PDB V7II86 399.3 Da LogP 1.34 TPSA 96.2 ✓ Ro5 ✓ Clean C[C@H]([C@@H](C(=O)NC/C=C/CN1C=Nc2cc(c(cc2C1=O)…
FQR RCSB PDB V7II86 430.7 Da LogP 1.62 TPSA 107.4 ✓ Ro5 ✓ Clean C[C@H]([C@@H](C(=O)OC/C=C/CN1C=Nc2cc(c(cc2C1=O)…
FQU RCSB PDB V7II86 446.7 Da LogP 2.23 TPSA 107.4 ✓ Ro5 ✓ Clean C[C@H]([C@@H](C(=O)OCCCCCN1C=Nc2cc(c(cc2C1=O)Cl…
SSA RCSB PDB P0A8M3 433.4 Da LogP -4.28 TPSA 238.0 2 viol. ✓ Clean c1nc(c2c(n1)n(cn2)[C@H]3[C@@H]([C@@H]([C@H](O3)…
TSB RCSB PDB P0A8M3 447.4 Da LogP -3.89 TPSA 238.0 2 viol. ✓ Clean C[C@H]([C@@H](C(=O)NS(=O)(=O)OC[C@@H]1[C@H]([C@…
X16 RCSB PDB P0A8M3 415.5 Da LogP 0.70 TPSA 161.3 ✓ Ro5 ✓ Clean Cc1nc2cc(ccc2c(n1)N)c3cccc(c3)S(=O)(=O)NC(=O)[C…

PDB and ChEMBL records on this protein are shown in full. ChEMBL records from similar proteins are capped at the top 100 per protein (by pchembl) and ZINC at the top 50 (Tanimoto ≥ 0.5). ADME columns are descriptor-based screening flags, not experimental toxicity results.

Cross-references

External database identifiers for this protein, its structures, ligands, and metabolic reactions.