UDP GLUCOSE: 4-(Β-D-GLUCOPYRANOSYLOXY)BENZOIC ACID GLUCOSYLTRANSFERASE FROM THE POLLEN OF PINUS DENSIFLORA

Article abstract of DOI:10.1016/0031-9422(89)80013-5

Exogenously supplied 4-hydroxybenzoic acid (HBA) was converted quantitatively to 4-(β-D- glucopyranosyloxy)benzoic acid (HBA glucoside) during 30 hr of germination of the pollen of Pinus densiflora (pine pollen). <14C-carboxyl>HBA(<14C>-HBA) was also converted to <14C>-HBA glucoside by pine pollen.UDP glucose: 4-(β-D-glucopyranosyloxy)benzoic acid glucosyltransferase from pine pollen was assayed by measuring the rate of formation of <14C>-HBA glucoside from <14C>-HBA and UDPG.The enzyme was partially purified from the pine pollen for the first.The M_r, of the enzyme was estimated to be ca 33 000 by Sephacryl S-300 gel filtration.The enzyme had a pH optimum at 7.5, and its activity was increased ca 50 and 60percent by the addition of 3 mM Ca(2+) and 0.1 mM EDTA, respectively.The K_m values for UDP glucose and 4-hydroxybenzoic acid were 2.4 x 1E-4 M and 2.9 x 1E-3 M, respectively.Key Word Index - Pinus densiflora; Pinaceae; Japanese red pine; pollen germination; pollen tube elongation; 4-hydroxybenzoic acid; 4-(β-D-glucopyranosyloxy)benzoic acid; UDPG; 4-(β-D-glucopyranosyloxy)benzoic acid glucosyltransferase