A novel method for detection of endo-xyloglucan transferase

A new approach has been developed for quantification of the activity of endo-xyloglucan transferase, a novel enzyme that mediates the transfer of a segment of one xyloglucan molecule to another xyloglucan molecule. Purified xyloglucans with defined molecular-weight distributions and their fluorescent derivatives (pyridylamino xyloglucans) were used as substrates for the en-zymatic reaction. The transferase activity was quantified by monitoring changes in molecular-weight distributions of substrates by an alkali compatible gel permeation chromatographic system, equipped with a pulsed amperometric detector and a fluorescence detector. This new method was applied to the rapid detection and characterization of a novel transferase derived from plant tissues. Key words: Cell wall — Endo-xyloglucan transferase — Pulsed amperometry detector — Pyridylamino xyloglucan — Vigna angularis Ohwi et Ohashi (azuki bean) — Xyloglucan. The plant cell wall is composed of crystalline microfi-brils embedded in a matrix of amorphous polymers (Alber-sheim 1976, Fry 1988). Xyloglucans (XGs) are the major components of the matrix and function as cross-links be