Biogenesis and Conversion of Wood Substance

木质物质在高等植物的木质部中形成木质细胞壁。本次合作研究将木材物质生物发生的研究扩展到转化利用的研究，19名研究人员分成5个小组。木质部分化和细胞壁木质化的分子研究：在分子水平上研究了单细胞木质部的分化，并对木质素的生物发生及其表达调控基因的研究取得了显著进展.细胞壁的结构与壁组分的生物发生的关系：在超微结构水平上研究了纤维素微纤丝、基质多糖和木质素的形成和沉积。对细胞壁的木质化过程进行了生物化学模拟.木材细胞壁的功能和物理特性与其形成的关系：分析了针叶树和阔叶树树干生长应力的产生与木材细胞壁成熟的关系.木质素的变异性和不均匀性：探讨了木质素不均匀性的各种原因.木材物质的化学转化、物理转化和生物转化：介绍了化学转化的一个实例和物理转化的方法。阐明了木材的生物降解机理，并将发表一份包括所有研究工作摘要的报告（日文）。

Wood substance makes lignified cell walls in xylem in higher plants. This co-operative research comprizes studies on biogenesis of wood substance to those on its conversions for use, and 19 investigators were grouped into 5 teams.1. Molecular aspects of xylem differentiation and lignification of cell wall : Xylem differentiation of isolated single cells were studied at molecular level, and studies on genes concerning biogenesis of lignin and on control of its expression were remarkably developed.2. Architecture of cell wall in relation to biogenesis of wall components : Formation and depositions of cellulose microfibrils, matrix polysaccharides and lignins were studied at ultrastructure levels. The process of lignification in the cell wall was also simulated biochemically.3. Function and physics of wood cellwall in relation to its formation : Generation of growth stresses in tree stems were analized in relation to the maturation of wood cell walls in needle- and broard-leaved trees.4. Variability and inhomogeneity of lignin : Various causes of inhomogeneity of lignin were investigated.5. Chemical, physical and biological convertibility of wood substance : An example of chemical conversion and a method of physical conversion were reported. The biological degradation mechanism of wood was clarified.A report which comprises summaries of all research works will be published (in Japanese).