KpATCC43816 Protein target profile

proton antiporter-2 family protein

Accession: VK055_3738

Gene: AIK82293.1 3D evidence: AlphaFold DB model + ColabFold model Metabolism Not in network UniProt A0A0H3H3Y3
Length 601
Pocket druggability (P2Rank · AlphaFold DB model) 0.767
Direct ligand evidence 0 54 total records
Functional annotation 0 EC 9 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 (%)
35.938 Lower values reduce human off-target concern.
Human E-value
1.95e-09
Gut microbiome similarity
2.5% of screened genomes Lower prevalence suggests narrower overlap with the screened gut microbiome.

Essentiality

Essential (DEG)
N
DEG identity (%)
35.621 Higher values support similarity to known essential genes.

Structure confidence

ColabFold pLDDT
84.0 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) 0.767
Structure A0A0H3H3Y3
Pocket Pocket 1
Druggability (FPocket) 0.763
Structure A0A0H3H3Y3
Pocket Pocket 14
ColabFold model
P2Rank 0.584 · Pocket 1
FPocket 0.897 · Pocket 56
Core conservation Conserved core gene
Roary core
CoreCruncher core
Gut microbiome 120 / 4744 genomes with a hit
Prevalence 2.5%

Metabolic context

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

This protein is not associated with the imported metabolic network for this genome.

Browse the genome's metabolic network

Imported from KpATCC43816.sbml · 2026-07-09

Sequence

Primary amino-acid sequence viewer.

MAGSDLLLAGVLFLFAAVIAVPLASRLGIGAVLGYLLAGIAIGPWGLGFISDVDEILHFSELGVVFLMFIIGLELNPAKLWRLRSSIFGVGAAQVMLSAAILGGLLMTTGFSWQAAVVGGIGLAMSSTAMALQLMREKGMSRSEAGQLGFSVLLFQDLAVIPALALVPLLAGSADEHVNWLTVGMKVLAFAGMLIGGRYLLRPVFRFIASSGVREVFTAATLLLVLGSALFMEALGLSMALGTFIAGVLLAESEYRHELEIAIDPFKGLLLGLFFISVGMALNLGVLYTHLLWVAVSVAVLVAVKMLVLYLLARLYGLRSSERMQFAGVLSQGGEFAFVLFSLPASQRLFQHDQMALLLVAVTLSMMTTPLLMKGIDKLLSRRLNPADDTGEAPWVEDDKPQVIIVGFGRFGQVIGRLLMANKMRITVLERDISAVNLMRNYGYKVYFGDATQLELLRSAGAEEAQSIVITCNEPEDTMRLVEMCQQHFPHLHILARARGRVEAHELLQAGVTQFSRETFSSALELGRKALITLGMHPHQAQRAQLHFRRLDMRMLRELMPVHTDTVQISRVREARRELEEIFQREMQKESRQLDGWDEFE

Functional annotations

Enzyme classification and Gene Ontology terms linked to this protein.

9 GO

Subcellular localization

Localization
CytoplasmicMembrane

Gene Ontology (GO)

9
  • GO:0016020 A lipid bilayer along with all the proteins and protein complexes embedded in it and attached to it.
  • GO:0006812 The directed movement of a monoatomic cation, into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. Monatomic cations (also called simple cations) are positively charged ions consisting of exactly one atom.
  • GO:0008324 Enables the transfer of cation from one side of a membrane to the other.
  • GO:0055085 The process in which a solute is transported across a lipid bilayer, from one side of a membrane to the other.
  • GO:0015503 Enables the transfer of a solute or solutes from one side of a membrane to the other according to the reaction: K+(in) + H+(out) = K+(out) + H+(in), where glutathione maintains the closed state.
  • GO:0005886 The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.
  • GO:1902600 The directed movement of a proton across a membrane.
  • GO:0015297 Enables the active transport of a solute across a membrane by a mechanism whereby two or more species are transported in opposite directions in a tightly coupled process not directly linked to a form of energy other than chemiosmotic energy. The reaction is: solute A(out) + solute B(in) = solute A(in) + solute B(out).
  • GO:0006813 The directed movement of potassium ions (K+) into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore.

Sequence domains and features

Domain and signature matches imported from InterPro and related databases.

58 records
Show feature table
Start End DB Term Name
147 171 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
6 25 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
324 343 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
108 112 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
374 601 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
29 51 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
344 354 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
26 31 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
402 530 SUPERFAMILY SSF51735 NAD(P)-binding Rossmann-fold domains
402 530 InterPro IPR036291 NAD(P)-binding domain superfamily
232 236 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
148 170 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
324 343 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
213 231 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
32 50 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
292 314 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
113 135 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
356 373 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
403 514 Pfam PF02254 TrkA-N domain
403 514 InterPro IPR003148 Regulator of K+ conductance, N-terminal
180 202 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
1 5 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
56 75 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
5 24 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
569 592 Coils Coil Coil
76 86 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
12 373 Pfam PF00999 Sodium/hydrogen exchanger family
12 373 InterPro IPR006153 Cation/H+ exchanger
313 323 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
56 73 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
172 182 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
3 385 FunFam G3DSA:1.20.1530.20:FF:000001 Glutathione-regulated potassium-efflux system protein KefB
267 286 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
113 135 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
292 312 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
223 245 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
5 589 PANTHER PTHR46157 K(+) EFFLUX ANTIPORTER 3, CHLOROPLASTIC
87 107 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
256 266 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
3 384 Gene3D G3DSA:1.20.1530.20 -
3 384 InterPro IPR038770 Sodium/solute symporter superfamily
355 373 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
14 283 NCBIfam TIGR00932 monovalent cation:proton antiporter-2 (CPA2) family protein
14 283 InterPro IPR004771 K+/H+ exchanger
51 55 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
136 146 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
237 255 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
402 524 ProSiteProfiles PS51201 RCK N-terminal domain profile.
402 524 InterPro IPR003148 Regulator of K+ conductance, N-terminal
265 287 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.
400 562 Gene3D G3DSA:3.40.50.720 -
202 212 Phobius CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the cytoplasm.
399 562 FunFam G3DSA:3.40.50.720:FF:000036 Glutathione-regulated potassium-efflux system protein KefB
183 201 Phobius TRANSMEMBRANE Region of a membrane-bound protein predicted to be embedded in the membrane.
2 598 Hamap MF_01412 Glutathione-regulated potassium-efflux system protein KefB [kefB].
2 598 InterPro IPR020884 Glutathione-regulated potassium-efflux system protein KefB
287 291 Phobius NON_CYTOPLASMIC_DOMAIN Region of a membrane-bound protein predicted to be outside the membrane, in the extracellular region.
86 108 TMHMM TMhelix Region of a membrane-bound protein predicted to be embedded in the membrane.

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
0.767
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Surrounding area
Pocket 2 P2Rank #2
0.394
Likely same site as FPocket 7 2.2 Å 13 shared residues 93% of smaller site
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Surrounding area
Pocket 3 P2Rank #3
0.348
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Surrounding area
Pocket 4 P2Rank #4
0.296
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Surrounding area
Pocket 5 P2Rank #5
0.212
Likely same site as FPocket 14 5.6 Å 13 shared residues 100% of smaller site
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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 #14
0.763
Likely same site as P2Rank 5 5.6 Å 13 shared residues 100% of smaller site
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Surrounding area
Pocket 2 FPocket #37
0.708
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Surrounding area
Pocket 3 FPocket #7
0.649
Likely same site as P2Rank 2 2.2 Å 13 shared residues 93% of smaller site
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Surrounding area
Pocket 4 FPocket #13
0.639
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Surrounding area
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_A0A0H3H3Y3
AlphaFold DB full sequence Viewing
ColabFold VK055_3738
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.

54 records
Chemistry signal

Structural ligand evidence is available for this target.

Direct evidence 0 same-protein records
Transferred evidence 4 records from similar proteins
Structural ligands 4 0 loaded crystals
Measured bioactivity 0 direct and transferred ChEMBL records
Proposed compounds 50 similarity-based ZINC candidates
Best available ligand signal
7E8 PDB via homolog 300.4 Da · LogP 3.36 · TPSA 66.8 Open detail RCSB PDB
ESG PDB via homolog Detail RCSB PDB
GSH PDB via homolog Detail RCSB PDB
L9X PDB via homolog Detail RCSB PDB
ZINC1501016272 ZINC proposed compound · Tanimoto 1.000 Detail ZINC

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
7E8 RCSB PDB Q5SIA2 300.4 Da LogP 3.36 TPSA 66.8 ✓ Ro5 ✓ Clean CCCCCC/C=C\CCCCCC(=O)OC[C@@H](CO)O
ESG RCSB PDB P03819 432.5 Da LogP -2.26 TPSA 196.2 ✓ Ro5 ✓ Clean CCN1C(=O)C[C@@H](C1=O)SC[C@@H](C(=O)NCC(=O)O)NC…
GSH RCSB PDB P03819 307.3 Da LogP -2.21 TPSA 158.8 1 viol. ✓ Clean C(CC(=O)N[C@@H](CS)C(=O)NCC(=O)O)[C@@H](C(=O)O)N
L9X RCSB PDB P03819 432.5 Da LogP -2.26 TPSA 196.2 ✓ Ro5 ✓ Clean CCN1C(=O)C[C@H](C1=O)SC[C@@H](C(=O)NCC(=O)O)NC(…

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.