Molecular characterization of Trypanosoma brucei rhodesiense putative oligosaccharyl transferase STT3 subunit (TbOST I).

摘要

Oligosaccharyl transferase functions as a catalyst for a complex carbohydrate-protein modification reaction, N-linked glycosylation, leading to the production of glycoproteins that contribute to its overall surface architecture. The molecular cloning and sequencing of putative Trypanosoma brucei rhodesiense oligosaccharyl transferase candidate was previously reported. Subsequently, described in this paper is the molecular characterization of a novel Trypanosoma brucei rhodesiense putative oligosaccharyl transferase STT3 subunit (TbOST I). A single-copy gene of TbOST I was established after Southern blot analysis. Northern hybridization revealed two (3.5 kb and 4.5 kb) mRNA transcripts in TbOST I. Immunoblot analysis exhibited that antibodies specific for the synthetic TbOST I oligopeptides reacted to ~50-55 kDa protein band. Furthermore, immunoflorescense test indicates a cytoplasmic and flagellar localization of TbOST I in Trypanosoma brucei rhodesiense bloodstream forms.