Characterization and Function of Bacterial Avirulence Genes
Considerable progress has occurred in the cloning and characterization of avirulence genes from viral and bacterial pathogens. All of the avirulence genes thus far cloned behave as single dominant alleles and encode unique protein products. Nevertheless, with one noteworthy exception, the functions of avirulence genes in the pathogens that harbor them are not known. The hypersensitive reaction (HR) in plants carrying the complementary avirulence gene, however, appears to be determined by elicitors— either primary avirulence gene protein products or metabolites arising from their catalytic activity. Since this topic has already been reviewed in depth (Keen et al., 1990; Keen, 1990), in this paper, I will concentrate only on the most recent information.
KeywordsGlycine Pseudomonas Microbe Rhizobium Erwinia
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