Heterologous overexpression of quorum-sensing regulators to study cell-density-dependent phenotypes in a symbiotic plant bacterium Mesorhizobium huakuii.
Quorum-sensing is widespread among many prokaryotic lineages. In order to investigate quorum regulation in the plant bacterium Mesorhizobium huakuii which produces an N-acyl homoserine lactone (AHL) quorum signal, the Agrobacterium quorum-sensing regulator TraR was heterologously expressed in this bacterium. The resulting strains showed reduced AHL production in the supernatant compared to wild-type, but similar intracellular levels of AHLs were detected, suggesting that M. huakuii AHLs can be bound to intracellular TraR proteins and thus become unavailable for its own quorum systems. M. huakuii overexpressing TraR formed thinner biofilms than the wild-type, suggesting a role played by quorum-sensing in biofilm formation.
Wang
Hui
H
Department of Microbiology, MOA Key Lab of Microbiological Engineering of Agricultural Environment, Nanjing Agricultural University, Nanjing, People's Republic of China.
Zhong
Zengtao
Z
Cai
Tao
T
Li
Shunpeng
S
Zhu
Jun
J
D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000096:biosynthesis; D020561:Alphaproteobacteria / Q000235:genetics / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D018441:Biofilms / Q000254:growth & development; D015964:Gene Expression Regulation, Bacterial; D011485:Protein Binding; D012231:Rhizobium / Q000235:genetics; D013559:Symbiosis
D001426:Bacterial Proteins; C080512:TraR protein, Agrobacterium tumefaciens; C088386:homoserine lactone; D015107:4-Butyrolactone