Figure 3. Xylooligomers of various lengths as acceptors for the xylosyltransferase activity of rice microsomes. The xylosyltransferase activity was assayed by incubating rice stem microsomes with UDP-xylose and the acceptor Xyl1-AA, Xyl2-AA, Xyl3-AA, Xyl4-AA, Xyl5-AA, or Xyl6-AA, and the reaction products were analyzed by reverse-phase HPLC and detected for fluorescent signals. The number at each peak denotes the number of xylosyl residues for the corresponding xylooligomer. A chromatogram of standard Xyl1–6-AA is shown at the top of each column for comparison of the xylooligomer peaks.