Lysosomes contain several integral membrane proteins (termed Lamps and Limps) that are
extensively glycosylated with asparagine-linked oligosaccharides. It has been postulated
that these glycans protect the underlying polypeptides from the proteolytic environment of
the lysosome. Previous attempts to test this hypothesis have been inconclusive because
they utilized approaches that prevent initial glycosylation and thereby impair protein folding.
We have used endoglycosidase H to remove the Asn-linked glycans from fully folded …