We studied the phosphorylation of the inner core region of N-linked oligosaccharides in the mannan defective mutant Saccharomyces cerevisiae mnn2 which was described as unable to synthesize branches on the outer chain. We performed structural studies of the N-oligosaccharides synthesized by the strains mnn2, mnn1mnn2mnn9 and mnn1mnn9ldb8, and the results are compared with previously published structural data of mnn1mnn2mnn10 and mnn1mnn9 [Hernandez, L.M., Ballou, L., Alvarado, E., Tsai, P.-K. and Ballou, C.E. (1989) J. Biol. Chem. 264, 13648-13659]. We conclude that the mnn2/ldb8 mutation is responsible for the inhibition of incorporation of phosphate to mannose A3 (see below), a particular phosphorylation site of the inner core, while phosphorylation at the other possible site (mannose C1) is allowed, although it is also reduced. Copyright (C) 2000 Federation of European Biochemical Societies.
Olivero, I., Mañas, P., & M. Hernández, L. (2000). The mnn2 mutant of Saccharomyces cerevisiae is affected in phosphorylation of N-linked oligosaccharides. FEBS Letters, 475(2), 111–116. https://doi.org/10.1016/S0014-5793(00)01635-5