Function and Regulation of Pectin-Degrading Enzymes in Bacterial Wilt Disease

  • C. Allen
  • J. Gay
  • Y. Guan
  • Q. Huang
  • J. Tans-Kersten
Chapter

Abstract

Virulence assays with various mutant strains indicate that extracellular polygalacturonases (PGs) contribute additively to bacterial wilt disease. However, pectinmethylesterase is not required for wild type virulence, at least on eggplants. Reaction product analysis shows that one PG, PehB, is an exo-poly-a-Dgalacturonosidase; further, the regulatory pehSR locus is required for wild type pehB expression. Genetic and biochemical evidence indicates that PehR is a response regulator of endo-polygalacturonase gene expression. In addition, the pehSR locus also regulates motility by a mechanism that is not yet understood.

Keywords

Sugar Agar Polysaccharide Pseudomonas Microbe 

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References

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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • C. Allen
  • J. Gay
  • Y. Guan
  • Q. Huang
  • J. Tans-Kersten

There are no affiliations available

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