Relationship Between Ultrastructural Topochemistry of Lignin and Wood Properties

Abstract

The main subunits of lignin could be visualized by transmission electron microscopy (TEM) with antibodies raised against synthetic lignin model polymers. Thus, immunological probes against p-hydroxyphenyl propane, guaiacyl and mixed guaiacyl-syringyl units allowed to specifically localize the qualitative distribution of lignins in plant cell tissues . Depending on the mode of preparation of the synthetic lignin antigens , the corresponding antibodies showed specificity for condensed or noncondensed interunits linkages . This specificity is illustrated with the different labellings provided by the antibodies when applied to various wood and nonwoody materials . The results c1early show the heterogeneity of lignification between tissues but also demonstrate the microheterogeneity of lignin deposition within a a single wood cell wall. Our immunological markers were successfully applied to transgenic plants in which lignin synthesis pathways had been modified, to tissues from reaction wood, as well as to materials degraded by ligninolytic fungi.