title: Characterization of a major sporozoite surface glycoprotein of Cryptosporidum parvum.
abstract: We have identified S60, a new Cryptosporidium parvum sporozoite surface glycoprotein. S60 was cleaved into two subunits, S16 and S45, approximately 16-18 and 45-47 kDa respectively, with cleavage occurring at an SRSRR motif likely to be sensitive to trypsin in vivo. Analysis by surface biotinylation, lectins and monoclonal antibodies suggests S60 is an abundant sporozoite surface glycoprotein that is shed by migrating sporozoites. The major glycosylation on S60 was identified as single O-linked N-acetylgalactosamine sugars on threonine and serine residues. The gene encoding the S60 protein was identified and revealed a C-terminal consensus sequence for the addition of a glycosylphosphatidyl inositol anchor. Antisera raised against recombinant S60 produced in Escherichia coli reacted with the surface of sporozoites and the inner wall of excysted oocysts.
authors.affiliation: Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Winter
authors.forename: A A
authors.initials: AA
authors.lastname: Gooley
authors.forename: K L
authors.initials: KL
authors.lastname: Williams
authors.forename: M B
authors.initials: MB
authors.lastname: Slade
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000953:Antigens, Protozoan / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D019921:Biotinylation; D015153:Blotting, Western; D016384:Consensus Sequence; D016785:Cryptosporidium parvum / Q000276:immunology*; D006031:Glycosylation; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D011994:Recombinant Proteins / Q000737:chemistry / Q000276:immunology; D020539:Sequence Analysis, Protein; D012694:Serine / Q000737:chemistry; D013170:Spores / Q000737:chemistry / Q000276:immunology; D013912:Threonine / Q000737:chemistry
chemical_list: D000911:Antibodies, Monoclonal; D000953:Antigens, Protozoan; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins; C448519:S60 glycoprotein, Cryptosporidum parvum; D013912:Threonine; D012694:Serine