Architecture Based Multiscale Computational Modeling of Plant Cell Wall Mechanics using Finite Element Method

Abstract

Structural cell wall polysaccharides have evolved to provide competing requirements of strength for plant cell wall to maintain shape vs. flexibility for growth. Understanding how plants mediate the cell wall mechanics to regulate cell development and growth will help in understanding how and why structural cell wall polysaccharides form cell wall networks. To understand the role and contribution of cell wall’s constituents, finite element model was developed for the plant cell wall mechanics with enough detail to incorporate the knowledge from nano-scale, yet large enough to provide framework for evaluating holistic mechanical response of plant cell wall using the multiscale approach. A set of mechanical properties of cellulose microfibrils (CMFs), hemicelluloses (HCs), and their interconnections were modeled at 1% strain in cell wall fragment’s elongation direction. Comparing cell wall networks with and without interconnection between those two polysaccharides (CMF and HC) showed that the introduction of interconnection description weakened cell wall network by up to two orders of magnitude. By estimating stiffness of interconnection with work done (strain energy) on connections, this approach enables examination of molecular structural models of cell wall network whose key hypotheses concerns interconnection characteristics of major structural polysaccharides.