Cell wall disassembly in ripening fruit

Fruit softening during ripening involves a coordinated series of modifications to the polysaccharide components of the primary cell wall and middle lamella, resulting in a weakening of the structure. Degradation of polysaccharides and alterations in the bonding between polymers cause an increase in cell separation and a softening and swelling of the wall, which, combined with alterations in turgor, bring about fruit softening and textural changes. A wide range in the extent of cell wall pectic modifications has been observed between species, whereas the depolymerisation of xyloglucan is relatively limited and more consistent. The earliest events to be initiated are usually a loss of pectic galactan side chains…