The photosensor protein Ppr of Rhodocista centenaria is linked to the chemotaxis signalling pathway

BMC Microbiology

Research Article

Sven Kreutel¹  Dorothee Kiefer¹  Andreas Kuhn¹ 

[1] Institute of Microbiology and Molecular Biology, University of Hohenheim, Garbenstrasse 30, D-70593, Stuttgart, Germany;

关键词: Histidine Kinase;    Chemotactic Response;    Phototactic Response;    Histidine Kinase Domain;    Phototrophic Purple Bacterium;   

DOI  :  10.1186/1471-2180-10-281

 received in 2010-03-28, accepted in 2010-11-09,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundRhodocista centenaria is a phototrophic α-proteobacterium exhibiting a phototactic behaviour visible as colony movement on agar plates directed to red light. As many phototrophic purple bacteria R. centenaria possesses a soluble photoactive yellow protein (Pyp). It exists as a long fusion protein, designated Ppr, consisting of three domains, the Pyp domain, a putative bilin binding domain (Bbd) and a histidine kinase domain (Pph). The Ppr protein is involved in the regulation of polyketide synthesis but it is still unclear, how this is connected to phototaxis and chemotaxis.ResultsTo elucidate the possible role of Ppr and Pph in the chemotactic network we studied the interaction with chemotactic proteins in vitro as well as in vivo. Matrix-assisted coelution experiments were performed to study the possible communication of the different putative binding partners. The kinase domain of the Ppr protein was found to interact with the chemotactic linker protein CheW. The formation of this complex was clearly ATP-dependent. Further results indicated that the Pph histidine kinase domain and CheW may form a complex with the chemotactic kinase CheAY suggesting a role of Ppr in the chemotaxis signalling pathway. In addition, when Ppr or Pph were expressed in Escherichia coli, the chemotactic response of the cells was dramatically affected.ConclusionsThe Ppr protein of Rhodocista centenaria directly interacts with the chemotactic protein CheW. This suggests a role of the Ppr protein in the regulation of the chemotactic response in addition to its role in chalcone synthesis.

【 授权许可】

Unknown   
© Kreutel et al; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.