D-glucosyltransferase that acts on the aglycone core, transferring D-glucose to the phenolic hydroxyl of OH-Phegly(4) to form a devancoaminyl-vancomycin (DVV) intermediate in the biosynthesis of glycopeptide antibiotic vancomycin. Also able to glycosylate A47934, an antibiotic with a teicoplanin-like heptapeptide, but lacking sugar residues. Antibiotic biosynthesis; vancomycin biosynthesis. In A.orientalis different glycosyltransferases are involved in biosynthesis of the vancomycin group of antibiotics. GtfA (AC P96558), GtfB (AC P96559) and GtfC (AC P96560) are involved in biosynthesis of antibiotic chloroeremomycin, while GtfD (AC Q9AFC7) and GtfE are involved in biosynthesis of vancomycin. Belongs to the glycosyltransferase 28 family.