| Characteristic | Summary for Q7NUH2 / CV_2726 | Evidence |
|---|---|---|
| Protein Name/ID | UniProt Q7NUH2; ordered locus name CV_2726; annotated as a probable transcriptional regulator, MarR family | UniProt-derived target description; genome-scale annotation of *C. violaceum* ATCC 12472 supports the presence of this locus in the sequenced strain (pqac-00000001, pqac-00000002) |
| Organism | *Chromobacterium violaceum* strain ATCC 12472 / DSM 30191 / JCM 1249 / CCUG 213 / NBRC 12614 / NCIMB 9131 / NCTC 9757 / MK | The complete genome sequence analyzed was from *C. violaceum* type strain ATCC 12472 (pqac-00000001) |
| Protein Family | MarR-family transcriptional regulator | MarR proteins are widespread bacterial transcription factors that generally act as repressors and often regulate stress-adaptive responses (pqac-00000003, pqac-00000005) |
| Key Domains | HTH_MarR-typ; MarR/SlyA-like; winged helix-turn-helix DNA-binding fold; MarR_2/PF12802 | MarR proteins characteristically contain a winged helix-turn-helix DNA-binding domain plus helices involved in dimerization (pqac-00000003, pqac-00000005, pqac-00000006) |
| Predicted Molecular Function | Sequence-specific DNA-binding transcriptional regulator, most likely functioning primarily as a repressor that modulates transcription of neighboring or regulon genes in response to chemical/redox signals | MarR-family proteins commonly repress transcription until ligand binding or oxidation lowers DNA affinity and derepresses target genes (pqac-00000003, pqac-00000006, pqac-00000008) |
| DNA Binding Characteristics | Likely homodimeric DNA-binding protein recognizing palindromic operator DNA, typically ~16–20 bp; recognition helices contact adjacent major grooves and the wing can contact the minor groove | General MarR-family DNA-binding mode and operator architecture are well established from structural and biochemical studies (pqac-00000003, pqac-00000005, pqac-00000006) |
| Signal/Ligand Sensing | Exact ligand for CV_2726 is unknown; by family analogy it may respond to small molecules such as phenolics, antibiotics, metals, or redox-active/oxidative signals that alter DNA-binding affinity | MarR-family regulators sense phenolic compounds, antibiotics, urate, metals, and oxidants; signaling commonly occurs through allosteric ligand binding or cysteine oxidation (pqac-00000007, pqac-00000008, pqac-00000010) |
| Biological Processes Regulated | Specific regulon for CV_2726 has not been experimentally defined; by family inference likely involved in environmental stress adaptation, potentially including oxidative stress responses, aromatic/xenobiotic metabolism, metal response, or virulence-associated regulation | In *C. violaceum*, the MarR-family regulator OhrR controls peroxide defense genes and virulence-related traits, while broader MarR-family literature links these regulators to oxidative stress resistance, aromatic compound degradation, exopolysaccharide/virulence control, and adaptive signaling pathways (pqac-00000010, pqac-00000011) |
| Subcellular Localization | Cytoplasmic DNA-binding regulator acting on chromosomal promoter/operator regions | MarR proteins act as intracellular transcription factors that bind target DNA in the bacterial cytoplasm/nucleoid compartment (pqac-00000003, pqac-00000005) |
| Evidence Type (experimental vs inferred) | Direct evidence for Q7NUH2/CV_2726: genome annotation/domain-based assignment; no direct functional study identified for this specific protein. Strong inferred evidence from conserved MarR-family structure-function relationships and from experimentally characterized MarR regulators in *C. violaceum* such as OhrR | Annotation and genome evidence are direct for locus existence; function, ligand sensing, and pathway roles are inferred from family/domain conservation and organism-level MarR studies (pqac-00000001, pqac-00000003, pqac-00000011) |


*Table: This table summarizes what is known directly and what can be inferred for Q7NUH2/CV_2726 in *Chromobacterium violaceum*. It is useful because direct literature on this exact protein is limited, so the table distinguishes annotation-supported facts from family-based functional inference.*