Journal article
Leishmania chagasi: uptake of iron bound to lactoferrin or transferrin requires an iron reductase
Experimental parasitology, Vol.100(3), pp.196-207
2002
DOI: 10.1016/S0014-4894(02)00018-8
PMID: 12173405
Abstract
Leishmania chagasi can utilize iron bound to transferrin, lactoferrin, or other chelates. We investigated the mechanism of iron uptake. Promastigotes preferentially took up iron in a reduced rather than an oxidized form, suggesting that extracellular iron must be reduced prior to internalization. Similar to literature reports, a 70-kDa protein in promastigote membrane-containing microsomes bound to [
125I]-labeled transferrin. However, [
125I]lactoferrin and [
125I]albumin also bound a similar 70-kDa protein, suggesting that binding might not be specific. Both total and fractionated promastigotes exhibited an NADPH-dependent iron reductase activity. In contrast to trypanosomes, which take up transferrin through a specific receptor, these data support a model in which a parasite-associated or secreted reductase reduces ferric to ferrous iron, decreasing its affinity for the extracellular chelate and allowing it to be readily internalized by the parasite. This could account for the ability of the parasite to utilize iron from multiple sources in diverse host environments.
Index Descriptors and Abbreviations.
Index descriptors: Cryptococcus neoformans,
Histoplasma capsulatum, iron, iron reductase, lactoferrin,
L. chagasi, leishmaniasis, nutrient acquisition, protozoan,
Saccharomyces cerevisiae,
Trypanosoma brucei,
Trypanosoma cruzi, transferrin;
Abbreviations used: DNA, deoxyribonucleic acid; DTT, dithiothreitol; HBSS, Hanks' balanced salt solution; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NEM,
N-ethylmaleimide; RNA, ribonucleic acid
Details
- Title: Subtitle
- Leishmania chagasi: uptake of iron bound to lactoferrin or transferrin requires an iron reductase
- Creators
- Mary E Wilson - Veterans' Affairs Medical Center, University of Iowa, Iowa City, IA 52242, USATroy S Lewis - Veterans' Affairs Medical Center, University of Iowa, Iowa City, IA 52242, USAMelissa A Miller - Veterans' Affairs Medical Center, University of Iowa, Iowa City, IA 52242, USAMichael L McCormick - Veterans' Affairs Medical Center, University of Iowa, Iowa City, IA 52242, USABradley E Britigan - Veterans' Affairs Medical Center, University of Iowa, Iowa City, IA 52242, USA
- Resource Type
- Journal article
- Publication Details
- Experimental parasitology, Vol.100(3), pp.196-207
- Publisher
- Elsevier Inc
- DOI
- 10.1016/S0014-4894(02)00018-8
- PMID
- 12173405
- ISSN
- 0014-4894
- eISSN
- 1090-2449
- Language
- English
- Date published
- 2002
- Academic Unit
- Microbiology and Immunology; International Programs; Epidemiology; Radiation Oncology; Internal Medicine
- Record Identifier
- 9984002388402771
Metrics
21 Record Views