Sugar Transport in Isolated Corn Root Protoplasts

Publisher Website
Google Scholar
Abstract
Isolated corn root protoplasts were used to study sucrose and hexose uptake. Glucose was preferentially taken up by the protoplasts over sucrose and other hexoses. Glucose uptake showed a biphasic dependence on external glucose concentration with saturable (Km or 7 mM) and linear components. Sucrose uptake only showed a linear kinetic curve. Sucrose and glucose uptake were linear over a minimum of 1 h at pH 6.0 and 1 mM exogenous sugar concentration. Glucose uptake showed a sharp 42.degree. C temperature optimum, while sucrose uptake showed a lower temperature sensitivity which did not reach a maximum below 50.degree. C. Uptake of both sugars was sensitive to several metabolic inhibitors and external pH. Differences between sucrose and glucose uptake in 2 different sink tissue (i.e., protoplasts from corn roots and soybean cotyledons) are discussed.

This publication has 22 references indexed in Scilit: