Radioiodination and identification of externally disposed membrane components of Leishmania tropica

摘要: Two methods, one involving a lactoperoxidase-glucose oxidase coupled reaction and the other employing insoluble catalyst 1,3,4,6-tetrachloro-3 α,6-α-diphenyl-glycoluril (Iodo-Gen), were used to label surface membrane of promastigotes Leishmania tropica major. Both methods labelled approximately 20 proteins or glycoproteins (apparent size range 10 110 kDa) in qualitatively similar manner, however lactoperoxidase method additional constituent (260 kDa). By omission both enzymes, Iodo-Gen; by comparison radioactivity incorporated particulate soluble cell fractions; through action proteases on live, promastigotes, surface-labelling specificity procedures was confirmed. Immunoprecipitation Triton X-100 extracts cells with rabbit antisera revealed minimum twelve (seven major) protein antigens homologous system different but cross-reactive species from two isolates L. tropica. Lectin precipitation radiolabelled components possible concanavalin A (but not lectins tested) identifying 12 glycoproteins. these (210 88 recognized antiserum.