Abstract
We report, here, the characterization of a mutant strain of Azospirillum brasilense Sp7 impaired in surface motility and chemotactic response. Presence of flagella in the mutant strain was confirmed by western blot analysis, using antisera raised against the polar and lateral flagellins, and by electron microscopy. Genetic complementation and nucleotide sequencing led to the identification of a new gene, named chsA. The deduced translation product, ChsA protein, contained a PAS sensory domain and an EAL domain. As ChsA displayed characteristic signaling protein architecture, it is thought that this protein is a component of the signaling pathway controlling chemotaxis in Azospirillum.
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Acknowledgments
The authors wish to thank Ms N. Desnoues and Ma. L. Xiqui for skillful technical assistance and Ms Jerri Bram for improving the language. This work was partially supported by a grant of VIEP-SEP.
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Communicated by Ursula Priefer.
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Carreño-López, R., Sánchez, A., Camargo, N. et al. Characterization of chsA, a new gene controlling the chemotactic response in Azospirillum brasilense Sp7. Arch Microbiol 191, 501–507 (2009). https://doi.org/10.1007/s00203-009-0475-x
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DOI: https://doi.org/10.1007/s00203-009-0475-x