Glycosylation of the major human Pneumocystis carinii surface antigen.
It has recently been shown that the major rat P. carinii surface antigen is important for initial host-organism attachment, possibly through binding to fibronectin, mannose-binding protein, or surfactant protein A. Since a carbohydrate/lectin interaction may be involved in adhesion, we undertook this study to characterize the glycosylation of the major human P. carinii surface glycoprotein (gp95). We have used purified gp95 as a source of antigen, and in lectin binding and deglycosylation studies it was found that approximately 9% of gp95 consists of N-linked carbohydrates of mainly high-mannose and bisected complex-type glycans. Using a polyclonal antibody raised against purified gp95 and crossed affinoimmunoelectrophoresis and the lectins Con A and WGA, gp95 exhibited carbohydrate-dependent microheterogeneity. We therefore suggest that gp95 is composed of subtypes which differ in N-linked glycosylation.
Lundgren
B
B
Department of Infectious Diseases and Microbiology, University of Copenhagen, Hvidovre Hospital, Denmark.
Koch
C
C
Mathiesen
L
L
Nielsen
J O
JO
Hansen
J E
JE
D000946:Antigens, Fungal / Q000378:metabolism*; D000954:Antigens, Surface / Q000378:metabolism*; D015153:Blotting, Western; D002448:Cell Adhesion; D003208:Concanavalin A; D004591:Electrophoresis, Polyacrylamide Gel; D006031:Glycosylation; D006801:Humans; D007123:Immunoelectrophoresis, Two-Dimensional; D008562:Membrane Glycoproteins / Q000378:metabolism; D011010:Pneumocystis / Q000276:immunology* / Q000502:physiology; D014909:Wheat Germ Agglutinins
D000946:Antigens, Fungal; D000954:Antigens, Surface; D008562:Membrane Glycoproteins; D014909:Wheat Germ Agglutinins; D003208:Concanavalin A