title: Selective cleavage of variant surface glycoproteins from Trypanosoma brucei.
abstract: Two conformationally distinct regions were revealed by tryptic cleavage of six undenatured variant surface glycoproteins purified from clones of Trypanosoma brucei. Within 5 min, the native glycoproteins (65,000 mol.wt.) were cleaved, yielding a large N-terminal fragment (48,000-55,000 mol.wt. depending on the variant) together with one or more C-terminal fragments. After 30-60 min incubation, further breakdown of the large fragment occurred in some variants. The ultimate large product (40,000-52,000 mol.wt.) was very resistant to further degradation by trypsin (in the absence of denaturation). The distinction between N-terminal and C-terminal domains may be significant in relation to the organization and function of these glycoproteins on the trypanosome surface.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002850:Chromatography, Gel; D005944:Glucosamine / Q000032:analysis; D006023:Glycoproteins; D010446:Peptide Fragments / Q000032:analysis; D014346:Trypanosoma brucei brucei / Q000032:analysis*; D014357:Trypsin
chemical_list: D000596:Amino Acids; D006023:Glycoproteins; D010446:Peptide Fragments; D014357:Trypsin; D005944:Glucosamine