Polysaccharides are ubiquitously present in the living world. They offer a great diversity of chemical structures ranging from simple linear homopolymers to branched heteropolymers. They are essential cellular constituents and their roles extend far beyond being mere energy stores (e.g. starch and glycogen) and structural support agents (e.g. cellulose and chitin). They partake in regulating cell wall plasticity (e.g. pectins, alginates and carrageenans), cell signaling, governing solution properties of some physiological fluids and participating in the structural build-up of the inter-cellular matrix (e.g. glycosaminoglycans), eliciting immune responses, cancer progression and as an anti-coagulating agent for the prevention of blood clots (e.g. heparin). Polysaccharides are frequently found on the cell surface of single-celled or multicellular organisms and in the extra-cellular matrix of eukaryotes and are involved in host-pathogen recognition events.Their structural versatility makes them important and interesting components in numerous biological processes ranging from structural stabilization to a variety of immunologically important molecular recognition events. The knowledge of polysaccharide three-dimensional (3D) structure is important in studying carbohydrate-mediated host-pathogen interactions, interactions with other bio-macromolecules, drug design and vaccine development.
The search period covered in this repository is about 50 years, during which these structural models have been proposed in the field of carbohydrate research. In view of the crucial role played by molecular modeling techniques, it was important to preserve, organize and distribute the macromolecular models developed. Their extensions to higher level of structures may expand our knowledge from the molecular to the microscopic level and help scrutinizing the several levels of structural organization of polysaccharides that underline their remarkable functions and properties. At a time when more and more carbohydrates and especially polysaccharides are being called to the fore for their increased use in a plethora of areas as diversified as tissue engineering and repair, wound healing, drug delivery systems, biofuels, bio-degradable fibers and bio-composites due to their generally non-toxic and biodegradable properties and being a renewable resource, PolySac3DB© shall be an asset to the community for probing further into the behavior of this class of biological macromolecules.
PolySac3DB© is established to maintain information on the detailed 3D structures of polysaccharides. All the data and features are available via the web-interface utilizing the search engine and can be accessed at this site using the panel on the left.