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Molecular analysis of the fur (ferric uptake regulator) gene of a pathogenic Edwardsiella tarda strain

  • Fang Wang
  • Shuang Cheng
  • Kun Sun
  • Li SunEmail author
Note

Abstract

The gene encoding the Edwardsiella tarda ferric uptake regulator (FurEt) was cloned from a pathogenic E. tarda strain isolated from diseased fish. FurEt shares 90% overall sequence identity with the Escherichia coli Fur (FurEc) and was able to complement the mutant phenotype of a fur Ec -defective E. coli strain. Mutational analysis indicated that C92S and C95S mutations inactivated FurEt whereas E112K mutation resulted in a superactive FurEt variant. FurEt negatively regulated its own expression; interruption of this regulation impaired bacterial growth, altered the production of certain outer membrane proteins, and attenuated bacterial virulence.

Keywords

Edwardsiella tarda Fur autoregulation virulence mutation 

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Copyright information

© The Microbiological Society of Korea and Springer-Verlag Berlin Heidelber GmbH 2008

Authors and Affiliations

  1. 1.Institute of OceanologyChinese Academy of SciencesQingdaoP. R. China
  2. 2.Graduate University of the Chinese Academy of SciencesBeijingP. R. China

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