title: Digitoxosyltetracenomycin C and glucosyltetracenomycin C, two novel elloramycin analogues obtained by exploring the sugar donor substrate specificity of glycosyltransferase ElmGT.
abstract: Our explorations of glycosyltransferase ElmGT from Streptomyces olivaceus Tü 2353, which shows an interesting flexibility regarding its sugar donor substrate, were extended toward various previously unexplored sugar co-substrates. The studies revealed that ElmGT, which normally transfers L-rhamnose to 8-demethyltetracenomycin C as a crucial biosynthetic step in elloramycin biosynthesis, is also able to process an activated non-deoxygenated sugar, NDP-D-glucose, as well as NDP-L-digitoxose, which is the first example of an NDP-L-sugar co-substrate of ElmGT possessing an axial 3-OH group. The structures of the resulting novel elloramycin analogues of these experiments, 8-demethyl-8-L-digitoxosyltetracenomycin C (4) and 8-demethyl-8-D-glucosyltetracenomycin C (7), were elucidated mainly by (1)H and (13)C NMR spectroscopy and by mass spectrometry.
authors.affiliation: Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, USA.
authors.forename: Carsten
authors.initials: C
authors.lastname: Fischer
authors.forename: Leticia
authors.initials: L
authors.lastname: Rodríguez
authors.forename: Eugenio P
authors.initials: EP
authors.lastname: Patallo
authors.forename: Fredilyn
authors.initials: F
authors.lastname: Lipata
authors.forename: Alfredo F
authors.initials: AF
authors.lastname: Braña
authors.forename: Carmen
authors.initials: C
authors.lastname: Méndez
authors.forename: Jose A
authors.initials: JA
authors.lastname: Salas
authors.forename: Jürgen
authors.initials: J
authors.lastname: Rohr
mesh_terms: D000880:Anthraquinones / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000378:metabolism; D002384:Catalysis; D016695:Glycosyltransferases / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D010957:Plasmids / Q000378:metabolism; D013302:Streptomyces / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D000880:Anthraquinones; D000900:Anti-Bacterial Agents; C471817:digitoxosyltetracenomycin C; C471816:glucosyltetracenomycin C; C047329:elloramycin; D016695:Glycosyltransferases