Table 3.
Diversity of single quorum sensing systems and signals in Gram-negative organisms
| Organism | Type of QSSa | Signal | Function | References |
|---|---|---|---|---|
| Pseudomonas corrrugata | PcoI/PcoR | C6HSL, C8HSL, 3OC6HSL | Virulence factor and lipodepsipeptides production | [73] |
| Pseudomonas mediterranea | PmeI/PmeR | C6HSL | Virulence factor and lipodepsipeptides production | [73] |
|
Pseudomonas putida
IsoF |
ppuI/ppuR | 3OC12HSL | Regulation of biofilm structural development | [109, 110] |
|
Pseudomonas putida
PCL1445 |
ppuI/rsaL/ppuR | 3OC12HSL | Production of cyclic lipopeptides: PutisolvinI and II | [111] |
| Pseudomonas syringae B728a | AhlI/AhlR | 3OC6HSL | Cell aggregation and epiphytic colonization for in planta growth and disease | [70] |
| Erwinia amylovora OMP-BO 1077/7 | EamI/EamR | 3OC6HSL | Virulence and secondary metabolites | [113] |
| Erwinia carotovora subsp. atroseptica SCRI1043 | ExpI/ExpR, VirR | 3OC6HSL | Production of exoenzymes and virulence, secretion of Nip and Svx proteins | [113] |
| Erwinia carotovora subsp. carotovora 71 | AhlI/ExpR, ExpR2 | 3OC6HSL | Production of exoenzymes and virulence | [113] |
| Erwinia carotovora subsp. carotovora ATCC 39048 | CarI/CarR, ExpR, VirR |
3OC6HSL | Production of carbapenem antibiotic, production of exoenzymes and virulence | [113] |
| Erwinia carotovora subsp. carotovora EC153 | AhlI/ExpR | 3OC8HSL (major), 3OC6HSL (minor) | Synthesis of plant cell wall degrading exoenzymes (proteases, pectinases, pectase lyases, cellulases) | [112] |
| Erwinia carotovora subsp. carotovora SCC3193 | ExpI/ExpR, ExpR2 | 3OC8HSL (major), 3OC6HSL (minor) | Synthesis of plant cell wall degrading exoenzymes (proteases, pectinases, pectase lyases, cellulases) and virulence | [113] |
| Erwinia carotovora subsp. carotovora SCRI193 | ExpI/ExpR, VirR | 3OC6HSL | Production of exoenzymes and virulence | [113] |
| Erwinia chrysanthemi 3937 | ExpI/ExpR | C6HSL, C10HSL, 3OC6HSL | Pectinase production | [113] |
| Serratia marcescens Strain 12 | SmaI/SmaR | C4HSL, C6HSL | Swarming motility, haemolytic activity, production of caseinase and chitinase, biofilm formation | [114] |
| Serratia marcescens MG1 | SwrI/SwrR | C4HSL (major), C6HSL (minor) | Attachment, serrawettin (a biosurfactant for swarming) production, protease protein production; butanediol fermentation and biofilm formation | [69] |
| Serratia marcescens SS-1 | SpnI/SpnR | C6 HSL, C7HSL, C8HSL, 3OC6HSL | Sliding motility, biosurfactant production; prodigiosin and nuclease production | [170] |
| Serratia plymuthica IC1270 | SplI/SplR | OHC6HSL, OHC8HSL | Negative regulation of biofilm formation | [116, 118] |
| Serratia plymuthica RVH1 | SplI/SplR | C4HSL, C6HSL, 3OC6HSL | Production of nuclease, chitinase, protease and antibacterial compound; butanediol fermentation | [117] |
| Serratia proteamaculans B5a | Sprl/SprR | C6HSL, 3OC6HSL | Production of lipase, protease and chitinase | [115] |
| Aeromonas hydrophila | AhyI/AhyR | C4HSL (major), C6HSL, C7HSL | Serine protease and metalloprotease production; biofilm maturation; Butanediol fermentation | [117, 119, 122] |
| Aeromonas salmonicida | AsaI/AsaR | C4HSL (major), C6HSL (minor) | Exoprotease production | [119, 122, 123] |
| Aeromonas salmonicida subsp. achromogenes | AsaI/AsaR | C4HSL | Virulence factors production (toxic protease AsaPI and cytotoxic factor) | [122] |
| Aeromonas sobria | AveI/AveR | C4HSL, C6HSL | Virulence | [121, 123] |
| Aeromonas veronii MTCC 3249 | AcuI/AcuR | C14HSL, 6-carboxy-HHL (homoadipyl -HSL), |
Virulence | [122] |
| Agrobacterium tumifaciens | TraI/TraZ | 3OC8HSL | Conjugal transfer of Ti plasmid | [6, 125] |
| Rhizobium etli strain CFN42 | TraI/TraR | 3OC8HSL, OHC8HSL | Plasmid transfer | [77] |
| Acinetobacter baumannii | AbaI/AbaR | C12HSL, C10HSL, C14HSL, C16HSL, 3OC13HSL, OHC12HSL | Biofilm formation and surface motility; virulence; production of antioxidant enzymes—catalase and superoxide dismutase | [134] |
| Brucella melitensis | VjbR, BlxR (orphan LuxR homologs) | C12HSL, 3OC12HSL | Surface modifications by regulating flagellar genes and type IV secretion system genes (virulence) | [133] |
| Hafnia alvei FB1 | Unreported | 3OC6HSL, 3OC8HSL | Food spoilage and biofilm formation | [130] |
| Halomonas anticariensis | HanI/HanR | C4HSL, C6HSL, C8HSL, C12HSL | Growth in extreme (Halophilic) environments | [137] |
| Pantoea agglomerans pv. gypsophilae | PagI/PagR | C4HSL (major), C6HSL (minor) | Virulence and gall development | [131] |
| Pantoea stewartii | EsaI/EsaR | 3OC6HSL | Exo/capsular polysaccharide synthesis; effective colonization of the host and virulence | [129] |
| Ralstonia solanacearum | SolI/SolR | C6HSL, C8HSL | Regulation of virulence by PhcA regulated pathway | [128] |
| Rhodobacter sphaeroides | CerI/CerR | 7,8-cis-N-C14HSL | Prevents aggregation of bacterial cells | [127] |
| Rhodopseudomonas palustris | RpaI/RpaR | p-coumaroyl-HSL (pC-HSL) | Activates novel rpaR antisense transcript | [143] |
| Helicobacter pylori | LuxS | AI-2 | Motility regulation, flagellar morphogenesis; AI-2 acts as a chemorepellant |
[144] |
| Klebsiella pneumoniae | LuxS | AI-2 | Regulation of biofilm formation and LPS synthesis | [141] |
| Porphyromonas gingivalis | LuxS | AI-2 | Modulate protease and haemagglutinating activity | [145] |
| Shigella flexneri | LuxS | AI-2 | Modulate expression of virulence genes | [140] |
| Xanthomonas campestris | DSF signalling system | DSF (diffusible signal factor): cis-11-methyl-2-dodecanoic acid | Regulation of virulence | [142] |
aQuorum sensing system