Biochemical and molecular characterization of sucrose and amino acid carriers in Ricinus communis

Abstract

The use of energized plasma membrane vesicle preparations from cotyledons and roots of Ricinus communis seedlings is described, and evidence is presented for the existence of plasma membrane H+/sucrose and H+/amino acid symporters. Using fractions isolated from roots, there is evidence for at least two carriers which can transport neutral amino acids and one which can also transport basic amino acids. A method for the solubilization and reconstitution of glutamine transport activity is described. Preliminary results on the molecular characterization of two putative amino acid carriers and a putative sucrose transporter from Ricinus are presented.