Cadmium Transport in Maize Root Segments Using a Classical Physiological Approach: Evidence of Influx Largely Exceeding Efflux in Subapical Regions.

ABSTRACT: The bidirectional fluxes of cadmium and calcium across the plasma membrane were assessed and compared in subapical maize root segments. This homogeneous material provides a simplified system for investigating ion fluxes in whole organs. The kinetic profile of cadmium influx was characterized by a combination of a saturable rectangular hyperbola (K_m = 30.15) and a straight line (k = 0.0013 L h^-1 g^-1 fresh weight), indicating the presence of multiple transport systems. In contrast, the influx of calcium was described by a simple Michaelis-Menten function (K_m = 26.57 µM). The addition of calcium to the medium reduced cadmium influx into the root segments, suggesting a competition between the two ions for the same transport syste

SUBMITTER: Rivetta A 

PROVIDER: S-EPMC10005225 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature