Latest news from the Designer Glycans research group at IPB Halle:
Research interests: Sugars! They are fundamental to all living cells. Plant cells are strengthened by carbohydrate-rich walls, and can thus survive in a wide range of environments. Since wall glycans make up the bulk of the plant biomass, they represent the most abundant renewable resource on Earth. In addition, cell walls are dynamic structures and play many critical functions throughout the plant life cycle. Our laboratory focuses on three outstanding questions in the field of glycobiology:
i) What are the control points for the elongation of polysaccharide backbones?
ii) What modulates the decoration of polysaccharides with specific branches?
iii) How do remodelled glycans impact the cell wall architecture and function?
Advances in these areas will pave the way for the assembly of sugar units into tailor-made structures with desirable properties for industrial applications.
Deciphering Heteromannan Biosynthesis
Plant cell walls primarily consist of cellulose microfibrils cross-linked by hemicellulose and, to a lesser extent, pectin. Junctions between these distinct classes of polysaccharides govern the biomechanical properties of the wall. Heteromannan (HM) is regarded as the most ancient hemicellulose, and is found throughout the plant kingdom. Despite their widespread distribution, the biosynthesis of HM polysaccharides has been grossly understudied relative to other plant cell wall components. The global demand for HM extracted from plant seeds has increased substantially in recent years due to its utility as an environmentally-friendly thickener in foods, cosmetics, and in many other industries. Furthermore, as the main component of the crema atop espresso, HM enhances the texture of the coffee beverage consumed by millions around the world on a daily basis.
Although the genomics era has ushered the identification of multiple genes involved in HM biosynthesis, most of them remain to be functionally characterized. Members of the Designer Glycans laboratory apply synthetic biology tools to gain mechanistic insight into HM biosynthesis, using yeast (such as Pichia pastoris) and Arabidopsis thaliana seed coat epidermal cells as model systems. Yeast cell walls lack hemicelluloses, but can be quickly engineered to produce large amounts of HM by expressing plant glycosyltransferases (Voiniciuc et al., 2019, PNAS).