cbrA (PP_4695, Q88DX3) review notes

Provenance

• Deep research: just deep-research PSEPK cbrA --provider falcon was attempted on 2026-10-23 and failed
  ("Failed to authenticate"); no other provider key is configured in this environment. The review is
  therefore built from UniProt and cached primary literature only. No -deep-research-*.md file exists.
• UniProt Q88DX3 is unreviewed and carries only the locus name PP_4695; the KT2440 literature names the
  locus cbrA PMID:32214184.

Function

• Sensor kinase: PMID:32214184
  No phosphatase activity PMID:32214184
• His766 is needed in vivo for crcZ activation PMID:32214184
• Transporter: PMID:32214184
  Corroborated in P. fluorescens SBW25 PMID:26148710
• The signal is unknown PMID:32214184
• Conservation beyond Pseudomonas: in Azotobacter vinelandii (Pseudomonadaceae) PMID:28404995

Curation decisions

• Accept GO:0000155 and GO:0000160 as core; general kinase/transferase/signal transduction terms are MODIFY to these.
• membrane -> plasma membrane; transporter terms refined to L-histidine (GO:0005290, GO:0089709).
• regulation of DNA-templated transcription (PAS InterPro2GO) marked over-annotated: CbrA acts on
  transcription only through CbrB.
• No NEW carbon catabolite repression row was added; the process is recorded on CbrB, whose activator
  output is the direct link to crcZ/crcY.