The aerobic respiratory chain of the acidophilic archaeon Ferroplasma acidiphilum: A membrane-bound complex oxidizing ferrous iron - Archive ouverte HAL Access content directly
Journal Articles Biochimica biophysica acta (BBA) - Bioenergetics Year : 2015

The aerobic respiratory chain of the acidophilic archaeon Ferroplasma acidiphilum: A membrane-bound complex oxidizing ferrous iron

(1) , (1, 2) , (3) , (1, 2) , (1, 4) , (5) , (5, 6) , (3, 1) , (1)
1
2
3
4
5
6

Abstract

The extremely acidophilic archaeon Ferroplasma acidiphilum is found in iron-rich biomining environments and is an important micro-organism in naturally occurring microbial communities in acid mine drainage. F. acidiphilum is an iron oxidizer that belongs to the order Thermoplasmatales (Euryarchaeota), which harbors the most extremely acidophilic micro-organisms known so far. At present, little is known about the nature or the structural and functional organization of the proteins in F. acidiphilum that impact the iron biogeochemical cycle. We combine here biochemical and biophysical techniques such as enzyme purification, activity measurements, proteomics and spectroscopy to characterize the iron oxidation pathway(s) in F. acidiphilum. We isolated two respiratory membrane protein complexes: a 850 kDa complex containing an aa3-type cytochrome oxidase and a blue copper protein, which directly oxidizes ferrous iron and reduces molecular oxygen, and a 150 kDa cytochrome ba complex likely composed of a di-heme cytochrome and a Rieske protein. We tentatively propose that both of these complexes are involved in iron oxidation respiratory chains, functioning in the so-called uphill and downhill electron flow pathways, consistent with autotrophic life. The cytochrome ba complex could possibly play a role in regenerating reducing equivalents by a reverse (‘uphill’) electron flow. This study constitutes the first detailed biochemical investigation of the metalloproteins that are potentially directly involved in iron-mediated energy conservation in a member of the acidophilic archaea of the genus Ferroplasma

Dates and versions

hal-01429900 , version 1 (09-01-2017)

Identifiers

Cite

Cindy Castelle, Magali Roger, Marielle Bauzan, Myriam Brugna, Sabrina Lignon, et al.. The aerobic respiratory chain of the acidophilic archaeon Ferroplasma acidiphilum: A membrane-bound complex oxidizing ferrous iron. Biochimica biophysica acta (BBA) - Bioenergetics, 2015, 1847 ( Issue 8), pp.717-728. ⟨10.1016/j.bbabio.2015.04.006⟩. ⟨hal-01429900⟩

Collections

CNRS UNIV-AMU
81 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More