ABSTRACT
This chapter first presents strategies for assaying diverse reactions that can modify cell-wall-related polysaccharides in vitro, under artificial conditions that are considered to mimic conditions in the walls of living plant cells. These reactions include those catalysed by glycanases, glycosidases, transglycanases, transglycosidases and lyases, and others that occur non-enzymically, such as oxidative scission by hydroxyl radicals and cross-linking by boron. This approach can provide interesting information about the types of reaction that might theoretically occur in vivo and thereby build and re-structure the cell wall’s architecture, with knock-on consequences for cell expansion, fruit ripening, abscission, etc. However, it is an important additional step to go from ‘might theoretically occur in vivo’ to ‘occur in vivo’, and this chapter places considerable emphasis on strategies for probing this issue. One of the key approaches in this direction is to monitor chemical changes that cell-wall polysaccharides undergo during the various stages of plant growth and development, and especially to document chemical ‘fingerprints’ that diagnose polysaccharide reactions that have recently occurred in vivo.
