The general phenylpropanoid metabolism generates an enormous array of secondary metabolites based on the few intermediates of the shikimate pathway as the core unit. The resulting hydroxycinnamic acids and esters are ...The general phenylpropanoid metabolism generates an enormous array of secondary metabolites based on the few intermediates of the shikimate pathway as the core unit. The resulting hydroxycinnamic acids and esters are am- plified in several cascades by a combination of reductases, oxygenases, and transferases to result in an organ and devel- opmentally specific pattern of metabolites, characteristic for each plant species. During the last decade, methodology driven targeted and non-targeted approaches in several plant species have enabled the identification of the participating enzymes of this complex biosynthetic machinery, and revealed numerous genes, enzymes, and metabolites essential for regulation and compartmentation. Considerable success in structural and computational biology, combined with the an- alytical sensitivity to detect even trace compounds and smallest changes in the metabolite, transcript, or enzyme pattern, has facilitated progress towards a comprehensive view of the plant response to its biotic and abiotic environment. Trans- genic approaches have been used to reveal insights into an apparently redundant gene and enzyme pattern required for functional integrity and plasticity of the various phenylpropanoid biosynthetic pathways. Nevertheless, the function and impact of all members of a gene family remain to be completely established. This review aims to give an update on the various facets of the general phenylpropanoid pathway, which is not only restricted to common lignin or flavonoid biosynthesis, but feeds into a variety of other aromatic metabolites like coumarins, phenolic volatiles, or hydrolyzable tannins.展开更多
Lignin with important biological functions is the second abundant natural product, its content is only less than cellulose in plant. But the lignin must be extracted from the cellulose fraction in making paper pulp pr...Lignin with important biological functions is the second abundant natural product, its content is only less than cellulose in plant. But the lignin must be extracted from the cellulose fraction in making paper pulp process leading energy_requiring, cost_increasing and pollution. Also, the lignin has negative effect on the digestibility of silage grass. So it is of considerable interest to reduce the lignin content in resource plants. The paper reviews the progress of lignin biosynthesis and regulation. The feasibility of reducing the lignin content and altering its composition for improving paper pulp production and decreasing pollution are discussed.展开更多
文摘The general phenylpropanoid metabolism generates an enormous array of secondary metabolites based on the few intermediates of the shikimate pathway as the core unit. The resulting hydroxycinnamic acids and esters are am- plified in several cascades by a combination of reductases, oxygenases, and transferases to result in an organ and devel- opmentally specific pattern of metabolites, characteristic for each plant species. During the last decade, methodology driven targeted and non-targeted approaches in several plant species have enabled the identification of the participating enzymes of this complex biosynthetic machinery, and revealed numerous genes, enzymes, and metabolites essential for regulation and compartmentation. Considerable success in structural and computational biology, combined with the an- alytical sensitivity to detect even trace compounds and smallest changes in the metabolite, transcript, or enzyme pattern, has facilitated progress towards a comprehensive view of the plant response to its biotic and abiotic environment. Trans- genic approaches have been used to reveal insights into an apparently redundant gene and enzyme pattern required for functional integrity and plasticity of the various phenylpropanoid biosynthetic pathways. Nevertheless, the function and impact of all members of a gene family remain to be completely established. This review aims to give an update on the various facets of the general phenylpropanoid pathway, which is not only restricted to common lignin or flavonoid biosynthesis, but feeds into a variety of other aromatic metabolites like coumarins, phenolic volatiles, or hydrolyzable tannins.
文摘Lignin with important biological functions is the second abundant natural product, its content is only less than cellulose in plant. But the lignin must be extracted from the cellulose fraction in making paper pulp process leading energy_requiring, cost_increasing and pollution. Also, the lignin has negative effect on the digestibility of silage grass. So it is of considerable interest to reduce the lignin content in resource plants. The paper reviews the progress of lignin biosynthesis and regulation. The feasibility of reducing the lignin content and altering its composition for improving paper pulp production and decreasing pollution are discussed.
