Improving polysaccharide performance using novel enzymes
Project Acronym: POLYMODE
Title of project: Novel polysaccharide modifying enzymes to optimise the potential of hydrocolloids for food and medical applications
Research area: Biotechnologies (Novel enzymes – the search for novel enzymes and micro-organisms for different bioprocesses)
Contract No: 222628
EU Contribution: 6000 000 EURO
Start date: May 2009
Duration: 48 Months
Polysaccharides are by far the most abundant biomolecules, they include well known glucose-based substances such as starch and cellulose as well as highly complex polymers that contain many different types of sugar. Such complex polymers are important ingredients for the food industries where they are used e.g. as thickeners to increase the viscosity of sauces or give texture to cheeses and ice cream. Such polymeric hydrocolloids are typically obtained from plants and algae. They include pectin that is mostly extracted from citrus peel, alginate from brown algae, and carrageenan and agar from red algae. Some hydrocolloids such as xanthan are produced by bacteria, while others such as chitosan are derived from shrimps and crabs, or from fungi. Related animal products include hyaluronan from cartilage and heparin from mucosa. In many cases, however, those hydrocolloids with the best properties are produced only from a few very specific organisms and are available only in limited quantities.
This project aims to identify, characterise, and optimise novel polysaccharide modifying enzymes and to develop robust fermentation strategies for their large-scale production. The potential uses of the modified biopolymers in food, pharmaceutical, cosmetic and technical applications will then be investigated. Two parallel approaches will be followed for various types of enzyme; a knowledge-based genomic or transciptomic approach and a broad un-biased metagenomic approach based on the use of soil or sludge samples with a history of contact with the polysaccharide in question. The project also aims to increase knowledge concerning the function of complex polysaccharides and the role they play in metabolic control, cellular and intercellular processes.
The project will impact on two distinct areas of application using enzymes to modify polysaccharides. The first approach which entails the modification of polymers produced in bulk by various organisms as structural or storage products should result in significant industrial impact in the short term. The polymers being investigated have a long history of commercial use. The aim of improving performance and substitution of high cost materials by ones of lower cost is relatively straight forward and can be implemented through use of conventional testing of modified product formulations looking at properties such as viscosity, gel stability, and compatibility with other ingredients, pH , ionic strength , etc. Success should lead to greater security of supply of such hydrocolloids through substitution of rarer ingredients or mimicking the properties of products which may be under threat through a combination of over-harvesting or pollution of wild sources. Substitution using such new products could also benefit consumers where lower cost modified hydrocollids can be substituted for those showing significant price increases.
The second approach of this project, that aims to elucidate the language and mechanism of cell recognition based on polysaccharide structures, will take much longer to have a significant impact. However, in the longer term, the impact could be much greater if it leads to pharmaceutical products or other methods that can change the nature or interaction of such cell wall based polymers. For example, it may become possible to modify such structures in organs used in transplant operations, reducing or eliminating the need for patients' life-long dependency on immuno-suppressive drugs as well as treat a wide range of diseases and disorders associated with the immune system.
This project will produce and use enzymes that modify polysaccharides.
It will produce results for six industrially important complex carbohydrates and indicate how their properties may be improved usingenzymes. The chosen polymers are alginate, carrageenan, chitosan, glycosaminoglycan, pectin, and xanthan gum. The enzymes that will be investigated include those able to modify, by synthesis or hydrolysis, patterns of substitution, e.g. different sulfatases and de-acetylases, transferases or debranching enzymes. Three levels of fermentation systems will be established, ranging from lab-scale expression systems through medium-scale, novel fermentations to established large-scale fermentation systems within the facilities of commercial partners. The application of these enzymes together with secondary enzymes, including sequence specific lyases and hydrolases, will enable the generation and analysis of polymers and oligomers with novel and defined, non-random patterns of modifications.
Results should indicate the extent to which the functional performance of the modified polymers is improved when used in existing food or health products. The project will also be identifying new uses, as well as ways of substituting more expensive polymers by modified lower cost polymers.
The project will also provide a better understanding of the molecular differences between various polymers that occur in cellular control systems or that affect interactions between cells of various organisms.
Using state-of-the-art mass spectrometry, the project will begin to unraveln this information system. The results will help resolve the complexity arising from the diversity of structures based on combinations of more than twenty 'letters' in the alphabet of sugars that link in various molecular configurations to form three dimensional branched structures. It will also identify, characterise, and optimise enzymes, using methods based on molecular genetics, for use in the synthesis or modification of such complex sugar structures in cell free system.
Website of project:www.polymode.eu
Coordinator: Bruno Moerschbacher, firstname.lastname@example.org
Organisation: University of Münster , Germany, www.uni-muenster.de
National Institute for Agricultural Research, France, www.international.inra.fr
National Centre for Scientific Research, France, www.cnrs.fr/index.php
Wageningen University, Netherlands, www.wur.nl/uk/
Swedish Agricultural University, Sweden, www.slu.se/en/
Bulgarian Academy of Sciences , Bulgaria, www.cu.bas.bg
Danisco A/S , Denmark, www.danisco.com
Sanofi-aventis Research & Development, France, www.sanofi-aventis.com
Gillet Chitosan Eurl, France and India, www.chitinindia.com
Geneart AG, Germany, www.geneart.com
Libragen, France, www.libragen.com/
ARTES Biotechnology GmbH, Germany, www.artes-biotechnology.com
GTP Technology, France, www.gtptech.com
Lyon Ingenierie Projets, France, www.lyoningenierie.fr
Care Sense Consulting, Germany