Figure 1.

Hypothetical effects of PMEs and PAEs on plant resistance: (1) Increased accessibility for pectin degrading enzymes, (2) production of more, smaller, and cross-linked OGs (DAMPs) that bind to WAKs and induce defense responses, (3) the release of free methanol or acetate that can be reincorporated in primary and secondary metabolism, (4) more negatively charged carboxyl groups that decrease the pH of the apoplast, and (5) more ROS-mediated pectin cross-linking with potential effects on ROS and calcium influxes into the cell.