TY - JOUR AU - Benziman, Moshe AB - Abstract In a recent paper (P Ohana, DP Delmer, JC Steffens, DE Matthews, R Mayer, M Benziman [1991] J Biol Chem 266: 13472-13475), we described the purification and structural characterization of β-furfuryl-β-glucoside (FG), an endogenous activator of plant UDP-glucose:(1→3)-β-glucan (callose) synthase. In the present report, we provide evidence that FG specifically stimulates callose synthase. The effects of FG on the kinetic properties of callose synthase were studied, and we ascertained that FG, or at least a very similar compound, is present in other plant systems. Chemically synthesized α-furfuryl-β-glucoside also stimulates callose synthase, exhibiting a slightly higher K a of 80 micromolar, compared with 50 micromolar for FG. In addition, we have identified and partially characterized an enzyme that catalyzes the synthesis of FG using β-furfuryl alcohol and UDP-glucose as substrates. A model for the regulation of callose synthesis in vivo, involving changes in intracellular compartmentation of FG and Ca2+, is proposed. 1 P.O. and M.B. were supported by Weyerhaeuser Company, D.P.D. by a contract from the U.S. Department of Energy, and J.C.S. and D.E.M. were supported by Hatch project 149417. This content is only available as a PDF. © 1992 American Society of Plant Biologists This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) TI - β-Furfuryl-β-Glucoside: An Endogenous Activator of Higher Plant UDP-Glucose:(1-3)-β-Glucan Synthase Biological Activity, Distribution, and in Vitro Synthesis JF - Plant Physiology DO - 10.1104/pp.98.2.708 DA - 1992-02-01 UR - https://www.deepdyve.com/lp/oxford-university-press/furfuryl-glucoside-an-endogenous-activator-of-higher-plant-udp-glucose-Dmo5hQCvij SP - 708 EP - 715 VL - 98 IS - 2 DP - DeepDyve ER -