HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Suchan, P. Articles by Tachezy, J. Search for Related Content PubMed PubMed Citation Articles by Suchan, P. Articles by Tachezy, J. Agricola Articles by Suchan, P. Articles by Tachezy, J.

Incorporation of iron into Tritrichomonas foetus cell compartments reveals ferredoxin as a major iron-binding protein in hydrogenosomes

Jií Petrák²

Robert ut'ák¹

Eva Nohnková³

Pavel Doleal¹

¹ Department of Parasitology, Faculty of Science, Charles University, Vininá 7, 128 44, Prague 2, Czech Republic
² Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 44, Prague 2, Czech Republic
³ Department of the Tropical Medicine, 1st Faculty of Medicine, Charles University, Faculty Hospital Bulovka, Studnikova 7, 128 00, Prague 2, Czech Republic
⁴ Johns Hopkins University, Bloomberg School of Public Health, W. Harry Feinstone Department of Molecular Microbiology and Immunology, 615 North Wolfe Street, Baltimore 21205, MD, USA

Correspondence
Jan Tachezy
tachezy{at}natur.cuni.cz

The intracellular transport of iron and its incorporation into organelles are poorly understood processes in eukaryotes and virtually unknown in parasitic protists. The transport of iron is of particular interest in trichomonads, which possess hydrogenosomes instead of mitochondria. The metabolic functions of hydrogenosomes, which contain a specific set of FeS proteins, entirely depend on iron acquisition. In this work the incorporation of iron into the cattle parasite Tritrichomonas foetus was monitored. Iron was efficiently taken up from ⁵⁹Fe-nitrilotriacetic acid and accumulated in the cytosol (88·9 %) and hydrogenosomes (4·7 % of the total radioactivity). Using atomic absorption spectrophotometry, an unusually high steady-state iron concentration in hydrogenosomes was determined [54·4±1·1 nmol Fe (mg protein)^-1]. The concentration of iron in the cytosol was 13·4±0·5 nmol Fe (mg protein)^-1. Qualitative analysis of incorporated iron was performed using native gradient PAGE. The majority of the ⁵⁹Fe in the cytosol appeared as the labile-iron pool, which represents weakly bound iron associated with compounds of molecular mass ranging from 5000 to 30 000 Da. Ferritin was not observed in Tt. foetus, nor in two other anaerobic protists, Entamoeba histolytica and Giardia intestinalis. Analysis of Tt. foetus hydrogenosomes showed at least nine iron-binding compounds, which were absent in metronidazole-resistant mutants. The major iron-binding compound was identified as [2Fe–2S] ferredoxin of the adrenodoxin type.

The GenBank accession number for the sequence reported in this paper is AF545472.

This article has been cited by other articles:

				N. Leon-Sicairos, M. Reyes-Lopez, A. Canizalez-Roman, R. M. Bermudez-Cruz, J. Serrano-Luna, R. Arroyo, and M. de la Garza Human hololactoferrin: endocytosis and use as an iron source by the parasite Entamoeba histolytica Microbiology, December 1, 2005; 151(12): 3859 - 3871. [Abstract] [Full Text] [PDF]

				R. Sutak, C. Chamot, J. Tachezy, J.-M. Camadro, and E. Lesuisse Siderophore and haem iron use by Tritrichomonas foetus Microbiology, December 1, 2004; 150(12): 3979 - 3987. [Abstract] [Full Text] [PDF]

				M. J. LaGier, J. Tachezy, F. Stejskal, K. Kutisova, and J. S. Keithly Mitochondrial-type iron-sulfur cluster biosynthesis genes (IscS and IscU) in the apicomplexan Cryptosporidium parvum Microbiology, December 1, 2003; 149(12): 3519 - 3530. [Abstract] [Full Text] [PDF]