Bacteriophage Mu as a genetic tool to study Erwinia amylovora pathogenicity and hypersensitive reaction on tobacco.

摘要: Erwinia amylovora 1430 was shown to be sensitive Mu G(-) particles. Infection resulted either in lytic development or lysogenic derivatives with insertion of the genome at many sites bacterial chromosome. We used d1Bx::Tn9 (lac Apr Cmr) derivative, called dX, identify mutants affected pathogenicity and their ability induce a hypersensitive reaction (HR) on tobacco plants. Inoculation 1,400 apple root calli led identification 12 three classes: (i) class 1 were nonpathogenic unable an HR plants; (ii) 2 but retained HR; (iii) 3 showed attenuated virulence. Of mutants, 8 had single dX prophage. For reversion concomitant loss Furthermore, revertants from also recovered Five six impaired exopolysaccharide production. No changes envelope structure (lipopolysaccharide outer membrane proteins) correlated differences pathogenicity. One mutant did not produce any functional siderophore, suggesting that iron uptake could involved Images