PECTINS IN WALLS OF PROTOPLAST-DERIVED CELLS IMBEDDED IN AGAROSE AND ALGINATE BEADS

Flax hypocotyl protoplasts were embedded in agarose and alginate heads . The pectin molecules of the formed colonies were observed in electro n microscopy using 2F4 antibody specific of a calcium-induced supramol ecular conformation of homopolygalacturonic acid. Little pectin, mostl y methylesterified, was present in agarose-entrapped colonies. The reg enerating cells immobilized in alginate secreted much higher amounts o f methylesterified pectins in their walls. De-esterification of the pe ctins was clearly seen after 6 days of culture. These results illustra te the importance of the external matrix on wall differentiation.