Leishmania amazonensis

From DrugPedia: A Wikipedia for Drug discovery

Leishmania amazonensis

The organisms are oval-shaped, and each has one long whip-like structure.

**Scientific classification**
Kingdom	Protista
Phylum	Euglenozoa
Class	Kinetoplastea
Order	Trypanosomatida
Family	Trypanosomatidae
Genus	Leishmania
Species	L. amazonensis
Binomial	Leishmania amazonensis

[edit] Surface Characteristics

The structure of cell surface glycosphingolipid is as follows : &alpha-Neup5Ac-(2-->3)-β-D-Galp-(1-->3)-β-D-GalpNAc-(1-->4)-β-D-Galp [branched to α-Neup5Ac-(2-->3)-] -(1-->4)-β-D-Glcp-(1-?)-CER-(?--/Ceramide/

[edit] Transmission

Leishmaniasis is transmitted by the bite of female phlebotomine sandflies. The sandflies inject the infective stage, metacyclic promastigotes, during blood meals (1). Metacyclic promastigotes that reach the puncture wound are phagocytized by macrophages (2) and transform into amastigotes (3). Amastigotes multiply in infected cells and affect different tissues, depending in part on which Leishmania species is involved (4). These differing tissue specificities cause the differing clinical manifestations of the various forms of leishmaniasis. Sandflies become infected during blood meals on an infected host when they ingest macrophages infected with amastigotes (5,6). In the sandfly's midgut, the parasites differentiate into promastigotes (7), which multiply, differentiate into metacyclic promastigotes and migrate to the proboscis (8).

Leishmaniasis is caused by infection with the pathogen Leishmania. The genomes of three Leishmania species (L. major, L. infantum and L. braziliensis) have been sequenced and this has provided much information about the biology of the parasite. For example it is now understood that in Leishmania protein-coding genes are organized as large polycistronic units in a head-to-head or tail-to-tail manner; RNA polymerase II transcribes long polycistronic messages in the absence of defined RNA pol II promoters; and Leishmania has unique features with respect to the regulation of gene expression in response to changes in the environment. The new knowledge from these studies may help identify new targets for urgently needed drugs, and aid the development of vaccines.

[edit] Pathogenic Activity

Leishmania amazonensis causes a wide spectrum of disease in humans. It is endemic in South America, where it causes cutaneous, diffuse cutaneous, and visceral leishmaniasis.