The SAS proposals for participation in FP6 projects
are listed in blocks according to the FP6 priority theme structure

FP6 priority
1.1.6   Sustainable Development, Global Change and Ecosystems
Title of the proposal

Novel Glycosyl Hydrolases and Esterases Involved in Plant Cell Wall Degradation

Slovak Academy of Sciences, Institute of Chemistry
Dubravska cesta 9, 84238 Bratislava, Slovak Republic
Dr. Peter BIELY
+421 2 59410275

Research subject for a potential FP6 project

The goal of the project is to provide new knowledge on microbial enzymes involved in the biodeg-radation of plant residues. Attention will be focused on new types of glycosyl hydrolases and esterases. The search for the new enzymes will be based on polysaccharides fragments and synthetic substrates not available on market. The desired compounds, corresponding to some of the recently described covalent linkages between plant cell wall components, such as polysaccha-rides and lignin, will be synthesized in the group. It is anticipated that the model compounds will not only enable to find enzymes with novel activities, but will also be used as substrates for determination of enzyme activities and for differentiation of enzymes of one type according to substrate specificities. An example is the synthesis of ferulic acid esters of a-L-arabinofurano-sides, b-D-xylopyranosides and b-D-galactopyranosides, as an alternative to tedious isolation of feruloylated oligosaccharides from natural materials as substrates for feruloyl esterases. The isolation of new enzymes will be the first step to isolation of the corresponding genes, to their cloning and overproduction of the enzymes in suitable host microorganisms. The enzymes will be tested for their role in plant cell wall digestion or plant tissue maceration. The results of such a project will have great impact on development of ecologically interesting and economically feasible processes of plant biomass utilisation. Eventually the project will introduce enzymatic procedures for isolation of plant cell wall components and important oligosaccharides applicable in areas related to human health and nutrition.

Recent international cooperation of the research team

Technical University of Athens, Greece (xylanases and esterases)
United States Department of Agriculture, ARS, Peoria, IL, USA (plant xylanolytic enzymes)
State University of Ghent, Belgium (xylanolytic enzymes and synthesis of substrtaes)
VTT Espoo, Finland (Trichoderma reesei glycosyl hydrolases and esterases)

Proposerīs relevant publications related to the research subject

1. Biely P., Hirsch J., la Grange D. C., van Zyl W. H., Prior B. A. (2000):
A chromogenic substrate for a b-xylosidase-coupled assay of a-glucuronidase.
Anal. Biochem. 286, 289-294.

2. Puchart V., Vrsanska M., Bhat M. K., Biely P. (2000):
Purification and characterization of a-galactosidase from a thermophilic fungus Thermomyces lanuginosus.
Biochim.Biophys. Acta 1524, 27-37.

3. Biely P, Puchart V., Cote G. L. (2001):
Enzymic a-galactosylation of cyclic glucotetrasaccharide derived from alternan.
Carbohydr. Res. 332, 299-303.

4. Mastihubova M., Biely P. (2001):
A common access to 2- and 3-substituted methyl b-D-xylopyranosides.
Tetrahedron Letters 42, 9065-9067.