Mechano-physical properties of the biopolymer callose: a matrix and a sealant?

The manufacture of many biodegradable and recyclable materials is based on the properties of natural biopolymers extracted from plant material (mainly cell walls). Cellulose is perhaps the most-well known example. The strength and extensibility of cellulose fibres is used in paper manufacturing, membrane technology, textiles and for the production of novel bandage materials. Other plant biopolymers (such as starch and pectins) also have important applications in the food industry, as stabilizers, thickeners, gelation agents and in pharmacology, as carriers for drug delivery or as bioactive agents in the treatment of cancer, cholesterol reduction, infection resistance and wound healing.
Clearly natural biopolymers have already made a positive impact on modern societies. With further understanding of their structural, chemical and physical properties, new industrial applications (for example in the development of novel biomaterials) can still emerge.
One biopolymer that has been little studied in this respect is called callose. It is a polysaccharide that occurs in plant cell walls with cellulose, the major component of paper. Callose accumulation is believed to seal off cell walls forming a defensive barrier against disease and other threats. It may also act as a matrix or scaffold by interacting with other cell wall polysaccharides. We know callose is important for plants because altered callose accumulation show negative effects in growth and development.
To get further insight on how callose functions we will first determine the physical properties of callose in solution and in mixtures with cellulose. Secondly, we will manipulate callose concentration in plant cell walls and detect changes in cell wall elasticity and in cell wall composition. Results from these analyses will indicate the role of callose in controlling the structural and mechanical properties of cell walls and identify new components that could be used to modify cellulose-base composites or to produce new environmentally friendly materials. Last but not least, the research will improve our understanding of the biological role of callose in cell walls. In the long term this knowledge could aid the development of biotechnological approaches to modify cell wall properties aiming to improve plant development and protection against environmental threats.

The research proposed here will reveal properties of the plant 1,3-beta glucan, callose, in cell walls. The benefits are many, it will: 1) contribute to our understanding of the mechano-physical properties of cell walls and on the factors that affects it, 2) provide knowledge for the development of tools to modify cell walls aiming to improve plant growth and protection, 3) reveal physical properties of callose and evidence of biopolymer interactions that, in the long term, could be applied in the development of new natural, biodegradable and recyclable composite materials for a variety of industrial applications.
1,3-beta glucans (extracted from bacteria and fungi) are already applied in pharmacology to increase host immunocompetency, but only recently, industries that utilize the structure-forming capabilities of these beta glucans have emerged. Thus, the infrastructure is in place to translate results from this research in economic benefits through its applications in fabricating new materials. An achievement of such nature will attract considerable international interest, industrial investments and strengthen the UK's scientific position.
In the shorter term, this project will have an impact:
-on the employability of the researchers involved by improving their scientific and transferrable skills and by supporting the establishment of inter-disciplinary collaborations with researchers in and outside the University.
-in the scientific community and the general public through advances in knowledge on the properties of callose in plant cell walls and in cellulose blends.
-on the wider scientific-business community, the UK government and policy makers through access to novel information with the potential to improve quality of life through its biotechnological applications and its potential for the development of new natural, biodegradable and recyclable composite materials.

Together with the Project Investigator (PI), the Co-I and the postdoctoral researcher (PDRA) will keep open lines of communication with the academic and business community and the public to disseminate the results from the research, and to explore opportunities to establish links for further applications of the results.

Pathways to generate impact during the lifetime of the grant are:
- Train a PDRA in both scientific and transferable skills and contribute to the education of undergraduate and Master students.
- Engage young audiences through UCAS and social media.
- Prepare and submit publications, present the work in conferences and establish/maintain new and existing collaborations.

In the medium/long term the PI and Co-I will participate in events to publicise to wider beneficiaries and establish links with business community to develop the project further and identify applications that could stimulate UK's economic growth and sustainable development.