Enzymic feruloylation of arabinoxylan-trisaccharide by feruloyl-CoA:arabinoxylan-trisaccharide O-hydroxycinnamoyl transferase from Oryza sativa.
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.
Yoshida-Shimokawa
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Forestry and Forest Products Research Institute, Tsukuba Norin Kenkyuu Danchinai, Ibaraki, Japan. tshimo@ffpri.affrc.go.jp
Yoshida
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S
Kakegawa
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Ishii
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T
D000215:Acylation; D000217:Acyltransferases / Q000378:metabolism*; D001089:Arabinose / Q000378:metabolism; D002473:Cell Wall; D002478:Cells, Cultured / Q000201:enzymology; D002851:Chromatography, High Pressure Liquid; D003373:Coumaric Acids / Q000378:metabolism; D012275:Oryza / Q000201:enzymology*; D014166:Transferases / Q000378:metabolism*; D014990:Xylans / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism
D003373:Coumaric Acids; D014990:Xylans; C085118:arabinoxylan; D014994:Xylose; C004999:ferulic acid; D001089:Arabinose; D014166:Transferases; D000217:Acyltransferases; C430668:feruloyl-CoA - arabinoxylan-trisaccharide O-hydroxycinnamoyl transferase