Introduction

Biosynthesis of Nucleotide Sugars for Cell Wall Polymers
Plant cell walls contain many different polymers, in particular cellulose, hemicellulose, pectic compounds and (structural) proteins. In the model plant Arabidopsis thaliana, approx. 50 % of the cell wall biomass is derived from the precursor UDP-glucuronic acid (UDP-GlcA). We are interested in the biosynthesis of UDP-GlcA, which occurs via two different pathways in plants. The pool of nucleotide sugars that is used to synthesize cell walls is well separated from nucleotide sugars which are used to synthesize sucrose, the major sugar in Arabidopsis transported into sink tissues.

Salvage pathways for sugars

Plants have established efficient recycling pathways for sugar, which are released from polymers or glycoproteins during growth and development. Sugars are toxic under certain conditions in plants. We are exploring the mechanisms behind sugar toxicity.

Methods
We are using different technologies to analyze the role of enzymes in sugar metabolism in growth and development. The technologies include e.g.: molecular genetics; knock-out plants  (T-DNA or CrisprCas); enzyme purification; a variety of expression systems for recombinant proteins; HPLC-analysis using different detector technologies like UV-diode array, electrochemical detection, conductivity; confocal microscopy; transgenic plants and mutants; realtime quantitative transcriptome analysis;…