cbcV (PP_0294) encodes the cytoplasmic ATP-binding (nucleotide-binding domain) subunit of the modular Cbc ABC importer of Pseudomonas putida KT2440. With the CbcW permease it forms the shared core that, depending on which periplasmic binding protein docks (CbcX, BetX or CaiX), imports choline, glycine betaine or L-carnitine. CbcV hydrolyzes ATP to power translocation; substrate specificity comes from the binding proteins.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0000166 nucleotide binding | IEA GO_REF:0000104 | MODIFY | Summary: Correct but less specific than ATP binding, which is already on this gene. Reason: CbcV is an ABC ATPase whose nucleotide-binding domain binds ATP. Proposed replacements: ATP binding Supporting Evidence: file:PSEPK/cbcV/cbcV-uniprot.txt PROSITE; PS00211; ABC_TRANSPORTER_1; 1. |
| GO:0005524 ATP binding | IEA GO_REF:0000120 | KEEP AS NON CORE | Summary: ATP binding by the CbcV nucleotide-binding domain; subsidiary to ATP hydrolysis. Reason: The ABC transporter signature establishes ATP binding; the term is as precise as warranted, but the core activity is ATP hydrolysis coupled to import. Supporting Evidence: file:PSEPK/cbcV/cbcV-uniprot.txt PROSITE; PS00211; ABC_TRANSPORTER_1; 1. |
| GO:0006970 response to osmotic stress | IEA GO_REF:0000117 | MARK AS OVER ANNOTATED | Summary: Osmotic-stress involvement is possible but not the established role of CbcV. Reason: Characterized Pseudomonas Cbc systems import quaternary amines for catabolism under low-osmolarity conditions; osmoprotection is not shown for this importer. Supporting Evidence: PMID:19919675 is required for the uptake of QACs under low-osmolarity conditions |
| GO:0015220 choline transmembrane transporter activity | IEA GO_REF:0000002 | ACCEPT | Summary: Correct activity of the CbcX-CbcWV complex that CbcV belongs to; the enables qualifier should be contributes_to. Reason: Choline transport is the right activity for the complex, which needs CbcW and the CbcX binding protein as well as the CbcV ATPase. The row is kept and the qualifier error recorded as a source defect, the convention used for the CbcW and CaiX (Q9HTH6) rows and for the BenB subunit in genes/ACIAD/benB. Supporting Evidence: PMID:19919675 In addition to the core transporter comprised of a transmembrane protein (CbcW) and an ATPase (CbcV), the Cbc transporter system interacts with at least three SBPs |
| GO:0015871 choline transport | IEA GO_REF:0000002 | ACCEPT | Summary: CbcV powers Cbc-dependent choline uptake. Reason: CbcWV with CbcX is the established choline importer in Pseudomonas; GO has no transmembrane child for choline transport. Supporting Evidence: PMID:19919675 CbcX, which binds choline with a high affinity and betaine with a much lower affinity |
| GO:0016887 ATP hydrolysis activity | IEA GO_REF:0000002 | ACCEPT | Summary: ATP hydrolysis is the direct catalytic function of CbcV. Reason: CbcV is the nucleotide-binding ATPase subunit of an ABC importer. Supporting Evidence: file:PSEPK/cbcV/cbcV-deep-research-openscientist.md cbcV encodes the ATP-hydrolyzing (nucleotide-binding) subunit file:PSEPK/cbcV/cbcV-uniprot.txt Pfam; PF00005; ABC_tran; 1. |
| GO:0055052 ATP-binding cassette (ABC) transporter complex, substrate-binding subunit-containing | IEA GO_REF:0000002 | ACCEPT | Summary: CbcV is the ATPase unit of a substrate-binding-protein-dependent ABC importer. Reason: CbcWV recruits interchangeable periplasmic binding proteins. Supporting Evidence: PMID:19919675 In addition to the core transporter comprised of a transmembrane protein (CbcW) and an ATPase (CbcV), the Cbc transporter system interacts with at least three SBPs |
| GO:0015226 carnitine transmembrane transporter activity | ISS PMID:19919675 The ATP-binding cassette transporter Cbc (choline/betaine/ca... | NEW | Summary: CbcV powers carnitine uptake when CbcWV is coupled to CaiX. Reason: CaiX supplies carnitine specificity to the shared CbcWV core. Supporting Evidence: PMID:19919675 demonstrating that CaiX was sufficient for, and specific to, carnitine uptake (Table 5). |
| GO:1902603 carnitine transmembrane transport | ISS PMID:19919675 The ATP-binding cassette transporter Cbc (choline/betaine/ca... | NEW | Summary: CbcV participates in CaiX-CbcWV carnitine import. Reason: The shared core is required for carnitine uptake in characterized Pseudomonas systems. Supporting Evidence: PMID:19919675 As expected, MKH13 cells coexpressing cbcWV (on pNcbcWV) and caiX (on a pTOK2T derivative) were able to take up carnitine but not choline and betaine |
Loading supporting content…
Download this section (compressed HTML)Q: Does KT2440 CbcV couple equally efficiently to CbcX, BetX, and CaiX assemblies?
Experiment: Reconstitute CbcWV with each substrate-binding protein and measure substrate-stimulated ATPase and uptake rates.
Type: transporter reconstitution
Loading supporting content…
Download this section (compressed HTML)Loading supporting content…
Download this section (compressed HTML)