chromobacterium subtsugae  (ATCC)

Journal: PLOS Pathogens

Article Title: Expanding the LuxR-type receptor functional repertoire: Protein-protein interactions in quorum sensing regulation

doi: 10.1371/journal.ppat.1014091

Figure Lengend Snippet: (A) Structural model of P. aeruginosa RhlR, highlighting the modular architecture that defines LuxR-type receptors: an N-terminal acyl-homoserine lactone (AHL) ligand-binding domain (LBD; turquoise) and a C-terminal helix-turn-helix (HTH) DNA-binding domain (DBD; yellow). The solvent-accessible volume of the LBD ligand-binding pocket is shown in light pink to provide structural context. Structures are derived from PDB IDs 8DQ0 and 8DQ1 , and all structure images were generated using ChimeraX. (B) Panel of AHL signal molecules recognized by the cognate receptors as in panel C. C4-HSL; P. aeruginosa ; RhlR, C6-HSL; C. subtsugae ; CviR, 3OC8-HSL; A. tumefaciens ; TraR, 3OC12-HSL; LasR; 3OHC12-HSL; A. baumannii ; AbaR. (C) Multiple sequence alignment (MSA) of LuxR-type receptors discussed in this review, spanning residues 44–72, which correspond to a conserved portion of the LBD. Amino acids are colored by physicochemical properties (positive, negative, polar, and non-polar, as indicated). A maximum-likelihood phylogenetic tree based on full-length sequences is shown to the left of the alignment. (D) Sequence alignment of the HTH DNA binding domains (residues 198–217) from the same set of receptors shown in panel B. The phylogenetic tree is omitted for clarity. Conserved residues within the HTH motif are denoted with an asterisk.

Article Snippet: In Chromobacterium subtsugae (formerly C. violaceum ATCC 31532), CviR activates violacein production and other virulence-associated genes in response to its cognate AHL [ ].

Techniques: Ligand Binding Assay, Binding Assay, Solvent, Derivative Assay, Generated, Sequencing

Journal: PLOS Pathogens

Article Title: Expanding the LuxR-type receptor functional repertoire: Protein-protein interactions in quorum sensing regulation

doi: 10.1371/journal.ppat.1014091

Figure Lengend Snippet: LuxR-type QS receptors (light-green ovals) are subject to regulation by a range of protein interaction partners (purple ovals), which modulate receptor function through distinct mechanisms. Negative regulators inhibit LuxR-type receptor function by disrupting dimerization, decreasing receptor stability, and inhibiting DNA binding. Representative examples include TraM-TraR ( A. tumefaciens ) , QscR-LasR/RhlR QteE-LasR/RhlR, Aqs1-LasR (all P.s aeruginosa ), and VioS-CviR ( C. subtsugae ). Dual or context-dependent regulators modify LuxR-type receptor activity in a promoter-, ligand-, or environmental-dependent manner. Examples include PqsE-RhlR ( P. aeruginosa ) and BlsA-AbaR ( A. baumannii ), which increase DNA binding affinity and/or transcriptional output under specific conditions. Global regulators modulate LuxR-type receptor function through transcriptional engagement or post-translational control, including RNA polymerase-mediated activation and protease-dependent receptor degradation. Created in BioRender. Paczkowski, J. (2026) https://BioRender.com/akj8r1w .

Article Snippet: In Chromobacterium subtsugae (formerly C. violaceum ATCC 31532), CviR activates violacein production and other virulence-associated genes in response to its cognate AHL [ ].

Techniques: Binding Assay, Activity Assay, Control, Activation Assay

Journal: Frontiers in Microbiology

Article Title: Commiphora myrrha resin extract inhibits the biofilms and quorum sensing controlled virulence factors of Gram-negative foodborne bacterial pathogens

doi: 10.3389/fmicb.2025.1668863

Figure Lengend Snippet: Quantitative determination of violacein inhibition in C. violaceum 12472 by sub-MICs of CMRE. Data is presented as mean of triplicates and bar denotes SD. Different letters above the bars indicate statistically significant differences among treatments ( p < 0.05). * depicts p ≤ 0.05 wrt to control and ** depicts p ≤ 0.01 wrt to control. Means denoted by the different letters within parameter are significantly different at p ≤0.05.

Article Snippet: In C. violaceum (ATCC 31532), the synthesis of violacein relies on QS, mediated by C 6 -AHL.

Techniques: Inhibition, Control