ACTIVE-TRANSPORT OF GLYCEROL-3-PHOSPHATE WITH ARTIFICIAL ENZYME MEMBRANES - A NEW KINETIC-MODEL FOR ACTIVE-TRANSPORT PROCESSES

An approach to the mechanism which may govern translocation and active transport system is presented. Two artificial enzyme membranes with i mmobilized kinase and immobilized phosphatase, respectively, were used close together to separate two unequal compartments of a specially de signed diffusion cell in order to mimic solute active transport. Exper iments were conducted and both translocation and active transport of g lycerol-3-phosphate were obtained. The theoretical analysis of this ac tive transport-like phenomenon, which underlines the key role played b y the charge distribution on the membrane and the diffusion layers exi sting close to the membrane-bound enzymes is presented and is in good agreement with the experimental data. Our results mainly demonstrate t hat under specific conditions, the association of kinase and phosphata se activities on both parts of a porous membrane functions as an enzym ic pump which performs active transport. Such results may be of genera l significance and lead us to suggest that a carrier could be substitu ted by two catalytic activities bound on both parts of a structure of channel type and catalysing two opposite reactions in diffusion layers .