Genetic reconstitution of the high-affinity L-arabinose transport system.

Expression plasmids containing various portions of araFGH operon sequences were assayed for their ability to facilitate the high-affinity L-arabinose transport process in a strain lacking the chromosomal copy of this operon. Accumulation studies demonstrated that the specific induction of all three operon coding sequences was necessary to restore high-affinity L-arabinose transport. Kinetic analysis of this genetically reconstituted transport system indicated that it functions with essentially wild-type parameters. Therefore, L-arabinose-binding protein-mediated transport appears to require only two inducible membrane-associated components (araG and araH) in addition to the binding protein (araF). Images