D-(+)-Fucose
D-(+)-Fucose is a nonmetabolizable analogue of l-arabinose. D-(+)-Fucose prevents growth of Escherichia coli B/r on a mineral salts medium plus l-arabinose by inhibiting induction of the l-arabinose operon. D-fucose is a potent inducer of beta-methylgalactoside permease (MGP)[1].