Related Experiment Video

Updated: Jun 27, 2026

Quantification of Intracellular Growth Inside Macrophages is a Fast and Reliable Method for Assessing the Virulence of Leishmania Parasites
10:01

Quantification of Intracellular Growth Inside Macrophages is a Fast and Reliable Method for Assessing the Virulence of Leishmania Parasites

Published on: March 16, 2018

Heme as a source of iron to Leishmania infantum amastigotes

Sandra Carvalho1, Tânia Cruz, Nuno Santarém

  • 1Instituto de Biologia Molecular e Celular, Porto, Portugal.

Acta Tropica
|November 18, 2008
PubMed

Insights

Leishmania parasites, the mammalian stage of Leishmania, can use hemin and hemoglobin for iron, not just ferrous iron. This dual iron acquisition strategy aids parasite survival during iron scarcity.

Area of Science:

  • Parasitology
  • Molecular Biology
  • Infectious Diseases

Background:

  • Leishmania amastigotes reside within macrophage parasitophorous vacuoles (PVs).
  • Parasites require iron for survival and proliferation.
  • Iron sources in the PV likely include heme and non-heme iron.

Purpose of the Study:

  • To investigate Leishmania amastigote's ability to utilize hemin and hemoglobin as iron sources.
  • To identify potential mechanisms for heme and hemoglobin uptake.
  • To understand the role of iron acquisition in Leishmania infection.

Main Methods:

  • Nutritional assays to assess iron utilization from hemin and hemoglobin.
  • Binding studies to characterize the interaction between amastigote surface ligands and hemin.
  • Comparative analysis of iron uptake pathways.

Main Results:

  • Leishmania amastigotes effectively utilize iron from hemin and hemoglobin, in addition to ferrous iron.
  • A high-affinity hemin-binding ligand (Kd=0.044nM) was identified on the amastigote surface.
  • Evidence suggests distinct mechanisms for hemin and hemoglobin internalization.

Conclusions:

  • Leishmania amastigotes possess multiple strategies for iron acquisition, including heme and hemoglobin.
  • A specific surface ligand facilitates hemin uptake.
  • These adaptable iron acquisition mechanisms likely enhance parasite infectivity and survival under iron-limited conditions.

More Related Videos

In Vivo Infection with Leishmania amazonensis to Evaluate Parasite Virulence in Mice06:57

In Vivo Infection with Leishmania amazonensis to Evaluate Parasite Virulence in Mice

Published on: February 20, 2020

In Vivo Imaging of Leishmania infantum-infected Hamsters by Gingival Inoculation of Axenic Amastigotes Expressing Luciferase05:55

In Vivo Imaging of Leishmania infantum-infected Hamsters by Gingival Inoculation of Axenic Amastigotes Expressing Luciferase

Published on: April 4, 2025

Related Concept Videos

Antiprotozoal Agents01:21

Antiprotozoal Agents

Leishmaniasis is a widespread parasitic disease caused by several Leishmania species. It affects millions of people each year and remains a major public health problem in endemic regions. First-line treatment relies on pentavalent antimonials, including meglumine antimoniate and sodium stibogluconate. Even so, how these drugs work has not been fully clear, especially their interaction with parasite-specific biochemical pathways. One key target is trypanothione reductase (TR), an enzyme that...
Leishmaniasis01:30

Leishmaniasis

Leishmaniasis is a protozoal disease caused by species of the genus Leishmania and transmitted through the bite of infected female sandflies. The parasite exists in two principal morphological forms during its life cycle. A sandfly acquires intracellular amastigotes from an infected reservoir host, such as a dog. Within the sandfly, these forms differentiate into motile, flagellated promastigotes. During a subsequent blood meal, promastigotes are injected into the human host, where they...
Amebiasis01:28

Amebiasis

Entamoeba histolytica, a protozoan parasite, is responsible for intestinal and extraintestinal amebiasis. Though a significant proportion of infections remain asymptomatic, approximately 50 million individuals annually are estimated to present with clinical disease, resulting in up to 100,000 deaths globally. The disease burden is disproportionately high in regions with lower socioeconomic status, such as parts of India, Africa, Mexico, and Latin America.Etiology and TransmissionThe infective...
The Early Endosome: Endocytosis of Transferrin01:28

The Early Endosome: Endocytosis of Transferrin

Essential proteins such as insulin or low-density lipoprotein (LDL) and micronutrients such as iron enter a eukaryotic cell through receptor-mediated endocytosis. Subsequently, the early endosomes fuse with the vesicles containing such receptor-ligand complexes and play a vital role in sorting the incoming ligands and receptors. While the ligands are either degraded inside the vesicle or released into the cytosol, their receptors are returned to the plasma membrane for further rounds of...
Lifecycle of Erythrocytes01:22

Lifecycle of Erythrocytes

Erythrocytes, also known as red blood cells, constantly move through blood capillaries. As a result, they damage their plasma membrane due to the continuous friction. Typically, after 100 to 120 days, erythrocytes become rigid and fragile as they wear out. As they pass through small vessels in the spleen and liver, they can get trapped and break apart into fragments.
The resident phagocytic macrophages deal with these damaged cells by engulfing them and separating their globin and heme groups.