Towards determining details of anaerobic growth coupled to ferric iron reduction by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1
Mark Dopson • Craig Baker-Austin • Philip Bond
Abstract
Elucidation of the different growth states of Ferroplasma species
is crucial in understanding the cycling of iron in acid leaching sites.
Therefore, a proteomic and biochemical study of anaerobic growth in 'Ferroplasma
acidarmanus' Fer1 has been carried out. Anaerobic growth in Ferroplasma
spp. occurred by coupling oxidation of organic carbon with the reduction
of Fe 3+; but sulfate, nitrate, sulfite, thiosulfate, and arsenate
were not utilized as electron acceptors. Rates of Fe3+ reduction
were similar to other acidophilic chemoorganotrophs. Analysis of the 'F.
acidarmanus' Fer1 proteome by 2-dimensional polyacrylamide gel electrophoresis
revealed ten key proteins linked with central metabolic pathways >4
fold up-regulated during anaerobic growth. These included proteins putatively
identified as associated with the reductive tricarboxylic acid pathway
used for anaerobic energy production, and others including a putative
flavoprotein involved in electron transport. Inhibition of anaerobic growth
and Fe3+ reduction by inhibitors suggests the involvement of
electron transport in Fe3+ reduction. This study has increased
the knowledge of anaerobic growth in this biotechnologically and environmentally
important acidophilic archaeon.
Mark Dopson
• Craig Baker-Austin • Philip Bond
School of Biological Sciences, University of East Anglia,
Norwich NR4 7TJ, UK
M. Dopson
Molecular Biology, Umea? University, 901 87 Umea, Sweden
P. Bond
Centre for Ecology, Evolution and Conservation,
University of East Anglia, Norwich NR4 7TJ, UK
Present address:
P. Bond
Advanced Wastewater Management Centre,
University of Queensland, Queensland 4072, Australia
E-mail: phil.bond@awmc.uq.edu.au
Present address:
C. Baker-Austin
Savannah River Ecology Laboratory,
University of Georgia, Aiken, SC, USA
SREL Reprint #2999
Dopson, M., C. Baker-Austin and P. Bond. 2007. Towards determining details of anaerobic growth coupled to ferric iron reduction by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1. Extremophiles 11:159-168.
