Abstract
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.
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Acknowledgments
We thank Dr Deb Hung and Yunrong Chai for helpful discussion and critically reviewing the manuscript. This study was supported by the NSFC Fund for Distinguished Young Scholars Fund (30325004), Fok Ying Tong Education Foundation (91023) [(to JZ)], the 973 project grant (001CB1089) and NSFC General Program (30200036) [(to ZZ)].
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Hui Wang and Zengtao Zhong contributed equally to this work.
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Wang, H., Zhong, Z., Cai, T. et al. Heterologous overexpression of quorum-sensing regulators to study cell-density-dependent phenotypes in a symbiotic plant bacterium Mesorhizobium huakuii. Arch Microbiol 182, 520–525 (2004). https://doi.org/10.1007/s00203-004-0735-8
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DOI: https://doi.org/10.1007/s00203-004-0735-8