TABLE 2.
AHL production in rhizobia
| Organism | AHL(s) present | System responsible for AHL production | Phenomenon regulated by quorum sensing | Reference(s) |
|---|---|---|---|---|
| A. tumefaciens | 3-Oxo-C8-HSL | traR/traI | Plasmid transfer | 62, 84, 130 |
| R. leguminosarum bv. viciae | C6-HSL | rhiR/rhiI | Nodulation efficiency | 29, 139 |
| C7-HSL | ||||
| C8-HSL | ||||
| 3-OH-C8-HSL | raiR/raiI | Unknown | 184 | |
| C6-HSL | ||||
| C7-HSL | ||||
| C8-HSL | ||||
| 3-Oxo-C8-HSLa | traR/traI | Plasmid transfer | 180 | |
| C8-HSLa | ||||
| 3-OH-C14:1-HSL | cinR/cinI | Growth inhibition | 95 | |
| R. etli CNPAF512 | Hydroxylated long chain AHL | cinR/cinI | Nitrogen fixation, symbiosome development, growth inhibition | 141 |
| Short-chain AHLs | raiR/raiI | Nitrogen fixation, growth inhibition | 30, 141 | |
| R. etli CFN42 | 3-Oxo-C8-HSLa | traR/traI | Plasmid transfer | 170 |
| 3-OH-C8-HSL | Unknown | Unknown | 170 | |
| Rhizobium sp. strain NGR234 | 3-Oxo-C8-HSLa | traR/traI | Plasmid transfer, growth inhibition | 78 |
| Other short-chain and long-chain AHLs | Unknown | Unknown | 78 | |
| S. meliloti Rm1021 | C12-HSL | sinR/sinI | Exopolysaccharide EPS II production | 107, 108; Marketon et al., submitted |
| 3-Oxo-C14-HSL | ||||
| C16:1-HSL | ||||
| 3-Oxo-C16:1-HSL | ||||
| C18-HSL | ||||
| C8-HSL | mel (putative) | Unknown | 108 | |
| Other short-chain AHLs | ||||
| S. meliloti Rm41 | 3-Oxo-C14-HSL | sinR/sinI | Exopolysaccharide EPS II production | 107; Marketon et al., submitted |
| C16-HSL | ||||
| C16:1-HSL | ||||
| 3-Oxo-C16:1-HSL | ||||
| 3-Oxo-C8-HSL | traR/traI | Plasmid transfer | 107; Marketon et al., submitted | |
| 3-OH-C8-HSL | ||||
| C8-HSL | ||||
| Other short-chain AHLs | mel (putative) | Unknown | Marketon et al., submitted | |
| Bradyrhizobium sp. | Bradyoxetinb | Unknown | Activation of nod genes | 96, 98, 99 |
a
AHL designation is based on thin-layer chromatography characteristics but has not been confirmed by mass spectrometry or nuclear magnetic resonance spectroscopy analysis.
b
Not a AHL.