The role of NDP-Glucose pyrophosphorylases in growing mung bean seedlings in relation to cell wall biosynthesis

Abstract

NDP-glucose pyrophosphorylase activities were measured in different parts of growing mung bean seedlings. Amongst the different enzymic activities only UDP-glucose pyrophosphorylase proved to be active, showing highest activity in the lower, no-longer elongating, sections of the hypocotyl. In contrast UDP-glucose : glucan synthetase activity was highest in the upper, still-elongating sections of the hypocotyl. Using hypocotyls of 2–6-day-old seedlings it could be demonstrated that UDP-glucose pyrophosphorylase activity was increasing as elongation ceased. At the same time UDP-glucose : glucan synthetase activity was decreasing.