NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

摘要: Blossoms are important sites of infection for Erwinia amylovora, the causal agent fire blight rosaceous plants. Before entering tissue, pathogen colonizes stigmatic surface and has to compete space nutrient resources within epiphytic community. Several epiphytes capable synthesizing antibiotics with which they antagonize phytopathogenic bacteria. Here, we report that a multidrug efflux transporter, designated NorM, E. amylovora confers tolerance toxin(s) produced by bacteria cocolonizing plant blossoms. According sequence comparisons, single-component pump NorM is member toxic compound extrusion protein family. The corresponding gene widely distributed among strains related plant-associated mediated resistance hydrophobic cationic compounds norfloxacin, ethidium bromide, berberine. A norM mutant was constructed exhibited full virulence on apple rootstock MM 106. However, it susceptible isolated from quince were identified as Pantoea agglomerans 16S rRNA analysis one-third all trees examined. promoter activity twofold greater at 18°C than 28°C. lower temperature seems be beneficial host because availability moisture necessary movement sites. Thus, might employ successful competition other microbes reach high population densities, particularly temperature.