Characterization of two glycosyltransferases involved in early glycosylation steps during biosynthesis of the antitumor polyketide mithramycin by Streptomyces argillaceus - Blanco, G; Fernández, E; Fernández, M J; Braña, A F; Weißbach, U; Künzel, E; Rohr, J; Méndez, C; Salas, J A (Mol Gen Genet, 2000)