title: Trans-sialidase and mucins of Trypanosoma cruzi: an important interplay for the parasite.
abstract: A dense glycocalix covers the surface of Trypanosoma cruzi, the agent of Chagas disease. Sialic acid in the surface of the parasite plays an important role in the infectious process, however, T. cruzi is unable to synthesize sialic acid or the usual donor CMP-sialic acid. Instead, T. cruzi expresses a unique enzyme, the trans-sialidase (TcTS) involved in the transfer of sialic acid from host glycoconjugates to mucins of the parasite. The mucins are the major glycoproteins in the insect stage epimastigotes and in the infective trypomastigotes. Both, the mucins and the TcTS are anchored to the plasma membrane by a glycosylphosphatidylinositol anchor. Thus, TcTS may be shed into the bloodstream of the mammal host by the action of a parasite phosphatidylinositol-phospholipase C, affecting the immune system. The composition and structure of the sugars in the parasite mucins is characteristic of each differentiation stage, also, interstrain variations were described for epimastigote mucins. This review focus on the characteristics of the interplay between the trans-sialidase and the mucins of T. cruzi and summarizes the known carbohydrate structures of the mucins.
authors.affiliation: CIHIDECAR, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón II, 1428 Buenos Aires, Argentina.
authors.forename: M Eugenia
authors.initials: ME
authors.lastname: Giorgi
authors.forename: Rosa M
authors.initials: RM
authors.lastname: de Lederkremer
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D014355:Chagas Disease / Q000378:metabolism / Q000469:parasitology; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology* / Q000627:therapeutic use; D006001:Glycoconjugates / Q000737:chemistry / Q000378:metabolism; D006023:Glycoproteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D006801:Humans; D008018:Life Cycle Stages; D008969:Molecular Sequence Data; D009077:Mucins / Q000737:chemistry / Q000378:metabolism*; D009439:Neuraminidase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011485:Protein Binding; D012794:Sialic Acids / Q000378:metabolism*; D013045:Species Specificity; D014349:Trypanosoma cruzi / Q000201:enzymology*; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D006001:Glycoconjugates; D006023:Glycoproteins; D017261:Glycosylphosphatidylinositols; D009077:Mucins; D012794:Sialic Acids; D010738:Type C Phospholipases; C069715:trans-sialidase; D009439:Neuraminidase