Pectin is a critical contributor to the mechanical properties of Chara cell walls
Cellulose has long been viewed as the major load-bearing component in plant primary cell walls. Recent studies, however, suggest that pectin plays a significant role in cell wall mechanics despite a kPa-scaled modulus. Here we quantify the mechanical properties of centimeter-sized internodal cell walls of Chara corallina following treatments to remove calcium crosslinks or digest pectin. We also…
Pectin, once considered secondary in importance to cellulose, plays a crucial role in the mechanical properties of Chara cell walls. Recent research has demonstrated that pectin significantly influences the elasticity and permeability of these cell walls, despite having a lower modulus compared to cellulose.
In a series of experiments, scientists manipulated the cell walls of Chara corallina by removing either calcium crosslinks or pectin. They found that eliminating calcium crosslinks did not affect the wall's strength or stress-relaxation behavior. However, removing pectin had a profound impact on the wall's mechanical performance.
Samples devoid of pectin displayed reduced strength and stiffness, along with increased stress relaxation under constant strain. More importantly, the removal of pectin led to a significant increase in the wall's permeability to both water and gas. This alteration was so pronounced that the pressure required for gas to tunnel through the cell wall was reduced by approximately two-fold.
These findings suggest that pectin acts as a local constraint on the movement of cellulose microfibrils within the cell wall. This function could have significant implications for the understanding of primary cell walls in vascular plants, as well as for the development of high-performance materials known as double-network materials.
Written by urgent.news from bioRxiv's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
