In a paper recently published in Plant Physiology we investigate the structure and function of one of an important component of plant biomass – galactoglucomannan (GGM). The GGM is a polysaccharide, a polymer made from multiple sugar molecules joined together. It is one of the principal components of softwood, wood from coniferous trees, which is the main construction timber used globally. In addition to that, GGM is also an important dietary component, used for example as a natural gelling agent.
In our work we have investigated the GGM secreted from seeds of a model plant Arbidopsis thaliana. The gel secreted from the seeds, also known as mucilage, is composed from multiple different polysaccharides which may interact, similarly to the polysaccharides found in wood. “We were surprised to discover that the structure of the polysaccharide found in mucilage is highly regular with repeating mannose and glucose sugars found over the majority of the polymer backbone” commented Dr Li Yu, the lead author of the study and a post-doctoral researcher at the Centre for Natural Material Innovation. “The regular structure of the GGM secreted from Arabidopsis seeds may enable it to interact with other polysaccharides, in particular with cellulose which is the main carbon based polymer on the planet” speculated Dr Yu. Indeed the molecular dynamic simulations, performed as part of the published work by collaborators of the NMI centre based at the University of Campinas in Brazil, indicated that the regular structure of GGM can interact stably with the cellulose crystal.
It is unclear if the discovered regular structure of GGM is present in wood. However, the techniques developed as part of the published study and insights gained from the molecular dynamics simulations may help increase our knowledge about the molecular architecture of plant natural materials.
Publication details:
Yu L, et al. The patterned structure of galactoglucomannan suggests it may bind to cellulose in seed mucilage. Plant Physiology 2017 in press
Open access full text available.
Profile of NMI researcher, Dr Li Yu
