1 Australian Research Council Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia.
2 Complex Carbohydrate Research Centre and Department of Biochemistry and Molecular Biology, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA.
3 Australian Research Council Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia, abacic@unimelb.edu.au.