Bacterial Kdp potassium-homeostasis system

A reusable bacterial module coupling KdpD/KdpE phosphorelay control to the high-affinity KdpFABC potassium pump. KdpD senses conditions associated with potassium limitation and phosphorylates KdpE, activated KdpE promotes kdpFABC transcription, and the membrane KdpFABC complex couples ATP hydrolysis to potassium uptake. Constitutive potassium channels and lower-affinity uptake systems are outside this module.

MODULE:bacterial_kdp_potassium_homeostasisDRAFTCONCRETEBiological Processmodules/bacterial_kdp_potassium_homeostasis.yaml
potassium ion homeostasisGO:0055075
PMID:10608856
The KdpF subunit is part of the K(+)-translocating Kdp complex of Escherichia coli and is responsible for stabilization of the complex in vitro
Biochemical deletion and reconstitution experiments establish KdpF as a complex-associated stabilizing element rather than an independently catalytic potassium transporter.
GO:0000160
phosphorelay signal transduction system
Defines the KdpD/KdpE two-component signaling relationship.
GO:0008556
P-type potassium transmembrane transporter activity
Defines ATP-coupled potassium transport by the KdpFABC pump.
file:PSEPK/kdpA/kdpA-ai-review.yaml
Grounds the PSEPK KdpA potassium-binding and translocation exemplar.
file:PSEPK/kdpB/kdpB-ai-review.yaml
Grounds the PSEPK KdpB P-type ATPase exemplar.
file:PSEPK/kdpC/kdpC-ai-review.yaml
Grounds the PSEPK KdpC accessory-subunit exemplar.
file:PSEPK/kdpD/kdpD-ai-review.yaml
Grounds the PSEPK KdpD sensor-kinase exemplar.
file:PSEPK/kdpE/kdpE-ai-review.yaml
Grounds the PSEPK KdpE response-regulator exemplar.
file:PSEPK/kdpF/kdpF-ai-review.yaml
Grounds the PSEPK KdpF stabilizing-subunit exemplar.

The module is species-neutral; Pseudomonas putida KT2440 proteins provide a concrete implementation. The environmental input to KdpD can integrate potassium limitation, ionic strength, and membrane-state signals differently among bacteria, so the first role is described conservatively. KdpC and KdpF are retained as pump components but are not assigned independent catalytic molecular functions. KdpF stabilization is grounded by E. coli biochemical evidence; conservation of that quantitative contribution in KT2440 remains inferential. InterPro:IPR011726 is used pragmatically for KdpF because this 29-residue membrane peptide has no PANTHER family assignment.

4Nodes
3Parts
0Variant Sets
0Variants
3Annotons
2Connections

Derived QC

Recommended-field compliance

60.0% recommended fields populated
  • module.knowledge_gaps[0] · status (0/1)
  • module.knowledge_gaps[0] · provenance (0/1)

Module deep research

✗ none found

No MODULE:bacterial_kdp_potassium_homeostasis deep-research report alongside the module YAML.

Leaf nodes lacking representative members

✓ every leaf node grounds to a representative protein.

Template conformance

✓ every declared conforms_to bundle matches its template motif.

Gene-review completeness (6/6 grounded genes reviewed)

6 complete review(s) · 1 with deep research · 0 missing review · 5 reviewed but lacking deep research

Gene Review Complete Deep research
kdpA Q88FD7 ✓ ✓ ✓
kdpB A0A140FWL1 ✓ ✓ ✗
kdpC Q88FD8 ✓ ✓ ✗
kdpD Q88FD9 ✓ ✓ ✗
kdpE Q88FE0 ✓ ✓ ✗
kdpF A0A140FWL2 ✓ ✓ ✗

Details

Context
bacteriaNCBITaxon:2
Bacterial Kdp potassium-homeostasis systemBiological Processbacterial_kdp_potassium_homeostasis
potassium ion homeostasisGO:0055075
Context
bacteriaNCBITaxon:2

Connections

KdpD-dependent phosphorylation activates KdpE.
Activated KdpE promotes production of the KdpFABC pump.
Part 1: KdpD sensor-kinase signaling
KdpD sensor-kinase signalingBiological Processkdpd_sensor_signaling

Annotons

KdpD phosphorelay sensor kinase
kdpd_sensor_kinase
Participant: Family: bacterial KdpD sensor-kinase family
Family:
bacterial KdpD sensor-kinase familyPANTHER:PTHR45569:SF1
Representative Members: KdpD (Pseudomonas putida KT2440)UniProtKB:Q88FD9

Function

phosphorelay sensor kinase activityGO:0000155

Processes

phosphorelay signal transduction systemGO:0000160

Locations

plasma membraneGO:0005886

Detects the physiological input and transfers phosphate through its histidine-kinase relay to KdpE.

Part 2: KdpE-dependent transcriptional activation
KdpE transcriptional responseBiological Processkdpe_transcriptional_response

Annotons

KdpE response regulator
kdpe_response_regulator
Participant: Family: bacterial KdpE response-regulator family
Family:
bacterial KdpE response-regulator familyPANTHER:PTHR48111:SF50
Representative Members: KdpE (Pseudomonas putida KT2440)UniProtKB:Q88FE0

Function

phosphorelay response regulator activityGO:0000156

Processes

positive regulation of DNA-templated transcriptionGO:0045893

Receives phosphate from KdpD and activates transcription of the Kdp pump genes under inducing conditions.

Part 3: ATP-coupled high-affinity potassium uptake
KdpFABC potassium pumpProtein Complexkdpfabc_potassium_pump

Annotons

KdpFABC P-type potassium transporter
kdpfabc_transport_activity
Participant: Protein Complex: bacterial KdpFABC potassium pump
Protein Complex:
bacterial KdpFABC potassium pump
Active units:
KdpA potassium-selective transport subunit
Participant: Family: KdpA family
Family:
KdpA familyPANTHER:PTHR30607:SF2
Representative Members: KdpA (Pseudomonas putida KT2440)UniProtKB:Q88FD7
Role: Selects and translocates potassium ions.
KdpB P-type ATPase subunit
Participant: Family: KdpB family
Family:
KdpB familyPANTHER:PTHR43743:SF1
Representative Members: KdpB (Pseudomonas putida KT2440)UniProtKB:A0A140FWL1
Role: Couples ATP hydrolysis to KdpA-mediated potassium transport.
Function:
ATP hydrolysis activityGO:0016887
KdpC accessory subunit
Participant: Family: KdpC family
Family:
KdpC familyPANTHER:PTHR30042:SF2
Representative Members: KdpC (Pseudomonas putida KT2440)UniProtKB:Q88FD8
Role: Membrane-associated accessory component of the pump.
KdpF stabilizing subunit
Participant: Family: KdpF family
Family:
KdpF familyInterPro:IPR011726
Representative Members: KdpF (Pseudomonas putida KT2440)UniProtKB:A0A140FWL2
Role: Small membrane component that stabilizes the KdpFABC complex.

Function

P-type potassium transmembrane transporter activityGO:0008556
Substrates: extracellular potassium ion ATP water
Products: cytoplasmic potassium ion ADP phosphate

Processes

potassium ion transmembrane transportGO:0071805

Locations

plasma membraneGO:0005886

Performs high-affinity ATP-driven potassium uptake after induction of the kdp pump genes.