Molecular Characterization of Erwinia carotovora hrpL, which Encodes an Alternate Sigma Factor
Many plant and animal pathogenic bacteria use the type III-secretion system to deliver virulence factors into host cells. It is becoming clear that the type III-secretion systems, in phytopathogenic and plant associated bacteria, are specifically used to transport Harpins, the elicitors of hypersensitive reaction (HR), as well as avirulence gene (avr) products, disease-specific (dsp) gene products and other accessory factors that could contribute to pathogenicity (3,1,8). It is, therefore, perhaps to be expected that hrp (gene for HR & pathogenicity), avr, dsp and other genes controlling host interaction are co-regulated by common signals, transcription factors including novel sigma factors, and post-transcription regulators.
KeywordsSigma Factor Avirulence Gene Alternate Sigma Factor Plant Associate Bacterium Erwinia Species
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Our research is supported by the National Science Foundation (grant MCB-9728505) and the Food for the 21st Century Program of the University of Missouri.
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