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  1. Wanderley de Souza

Published Online: 15 SEP 2011

DOI: 10.1002/9780470015902.a0001974.pub2



How to Cite

de Souza, W. 2011. Trypanosoma. eLS. .

Author Information

  1. Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil

Publication History

  1. Published Online: 15 SEP 2011


The trypanosomes comprise a large number of species of pathogenic protozoa of animals and plants. Some present a simple life cycle in the insect; others, however, present a complex life cycle involving vertebrate and invertebrate hosts, with the participation of different developmental stages, some of which are localised within cells of the vertebrate host. These organisms present some characteristic features such as the presence of the kinetoplast, a highly specialised organisation of mitochondrial DNA, compartmentalisation of the glycolytic pathway in glycosomes, the presence of a network of filaments forming the paraflagellar rod connected to the flagelar axonme.

Key Concepts

  • Ideally the identification and classification of protozoa shall combine the use of classical taxonomic parameters with phylogenetic analysis.

  • Despite significant advances in biomedical sciences diseases caused by protozoa still constitute important health problem throughout the world.

  • Cell transformation in response to environmental factors is fundamental for parasitic protozoa survival both in the vertebrate and invertebrate hosts.

  • Intracellular parasites developed the ability to attach to host cell surface and to trigger various mechanism leading to their internalisation into the cells.

  • Endocytosis in protozoa of the Trypanosomatidae family is a highly polarised taking place only in the flagellar pocket and the cytostome.

  • In some protozoa the glycolytic pathway does not take place in the cytosol but is compartmentalised in an organelle known as glycosome, which is part of the family of organelles designated as peroxisome.

  • Protozoa of the Trypanosomatidae family may contain up to 30% of the total DNA concentrated in a special region of its unique mitochondrion, localised close to the origin of the flagellum, and known as the kinetoplast.


  • Trypanosoma;
  • Leishmania;
  • Phytomonas;
  • kinetoplast;
  • glycosome