Biochemical Characterization of Animal Cell Glycosylation Mutants

A wide variety of selection protocols gives rise to mutants with a primary defect in glycosylation. These include selections for resistance to plant lectins, reduced incorporation of 3H-labeled sugars, altered cellular adhesive properties, and selections against the functional activity or the presence at the cell surface of specific membrane molecules. This chapter discusses general strategies for the biochemical characterization of animal cell glycosylation mutants. Emphasis is made on the approaches used in characterizing Chinese hamster ovary (CHO) cell mutants. The chapter also refers experimental methods in the text without details because of the large number of different techniques involved and essentially all of them being standard. There is an outline of the strategies applied to the characterization of CHO glycocyslation mutants, with advantages and disadvantages of each approach. There are also some alternative approaches to deciding whether a new isolate is glycosylation defective.