Yoshida-Shimokawa T, Yoshida S, Kakegawa K, Ishii T
Forestry and Forest Products Research Institute, Tsukuba Norin Kenkyuu Danchinai, Ibaraki, Japan.
Planta. 2001 Feb;212(3):470-4. doi: 10.1007/s004250000490.
Feruloyl-CoA:arabinoxylan-trisaccharide O-hydroxycinnamoyl transferase, which catalyzes the transfer of ferulic acid from Fer-CoA to arabinoxylan-trisaccharide in the formation of feruloyl arabinoxylan-trisaccharide (Fer-AXX), has been found in an ionically bound fraction and a cytosol fraction of suspension-cultured rice (Oriza sativa L. cv. Nipponbare) cells. Analysis of reaction products by high-performance liquid chromatography showed the formation of product A, which is one of the transfer products having the same retention time as authentic Fer-AXX. Product A was purified by reverse-phase chromatographies to characterize its structure. The isolated product A showed the same ultraviolet spectrum and molecular weight on fast atom bombardment mass spectrometric analysis as those of authentic Fer-AXX. Alakaline saponification of product A released ferulic acid and oligosaccharide. The released oligosaccharide consisted of arabinose and xylose in a molar ratio of 1:2. These results support the identity of product A as feruloylated arabinoxylan-trisaccharide and show the existence of a feruloyltransferase catalyzing the feruloylation of a hemicellulosic fragment.
阿魏酰辅酶A：阿拉伯木聚糖三糖O - 羟基肉桂酰转移酶可催化阿魏酸从阿魏酰辅酶A转移至阿拉伯木聚糖三糖，形成阿魏酰阿拉伯木聚糖三糖（Fer - AXX）。在悬浮培养的水稻（Oriza sativa L. cv. Nipponbare）细胞的离子结合组分和胞质溶胶组分中已发现该酶。通过高效液相色谱对反应产物进行分析，结果显示形成了产物A，它是与纯品Fer - AXX保留时间相同的转移产物之一。通过反相色谱法对产物A进行纯化以表征其结构。在快速原子轰击质谱分析中，分离得到的产物A显示出与纯品Fer - AXX相同的紫外光谱和分子量。产物A经碱性皂化后释放出阿魏酸和寡糖。释放出的寡糖由阿拉伯糖和木糖组成，摩尔比为1:2。这些结果支持产物A为阿魏酰化阿拉伯木聚糖三糖，并表明存在催化半纤维素片段阿魏酰化的阿魏酰转移酶。
