Figure 15.

Chemical equation that represents the first interaction between endophytic bacteria and plant cells. In this interaction microbes produce and secrete ethylene onto plant cells. Ethylene triggers the plant cell to grow, release nutrients and release superoxide from NADPH oxidases (Nicotinamide Adenine Dinucleotide Phosphate Oxidases) on the plant cell plasma membrane. Some of the superoxide oxidizes cell walls from bacteria, induces nutrient leakage and may degrade them. Some of the superoxide reacts with ethylene to produce hydrogen peroxide and carbon dioxide. Reactants and products detected in histochemical analyses are indicated in red.