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Title: Extreme arsenic resistance by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1

Abstract

'Ferroplasma acidarmanus' Fer1 is an arsenic-hypertolerant acidophilic archaeon isolated from the Iron Mountain mine, California; a site characterized by heavy metals contamination. The presence of up to 10 g arsenate per litre [As(V); 133 mM] did not significantly reduce growth yields, whereas between 5 and 10 g arsenite per litre [As(III); 67-133 mM] significantly reduced the yield. Previous bioinformatic analysis indicates that 'F. acidarmanus' Fer1 has only two predicted genes involved in arsenic resistance and lacks a recognizable gene for an arsenate reductase. Biochemical analysis suggests that 'F. acidarmanus' Fer1 does not reduce arsenate indicating that 'F. acidarmanus' Fer1 has an alternative resistance mechanism to arsenate other than reduction to arsenite and efflux. Primer extension analysis of the putative ars transcriptional regulator (arsR) and efflux pump (arsB) demonstrated that these genes are co-transcribed, and expressed in response to arsenite, but not arsenate. Two-dimensional polyacrylamide gel electrophoresis analysis of 'F. acidarmanus' Fer1 cells exposed to arsenite revealed enhanced expression of proteins associated with protein refolding, including the thermosome Group II HSP60 family chaperonin and HSP70 DnaK type heat shock proteins. This report represents the first molecular and proteomic study of arsenic resistance in an acidophilic archaeon.

Authors:
Publication Date:
Research Org.:
Savannah River Ecology Laboratory (SREL), Aiken, SC
Sponsoring Org.:
USDOE
OSTI Identifier:
908667
Report Number(s):
SREL-3036
TRN: US200722%%853
DOE Contract Number:
DE-FC09-07SR22506
Resource Type:
Journal Article
Resource Relation:
Journal Name: Extremophiles; Journal Volume: 11
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; ARSENATES; ARSENIC; CALIFORNIA; CONTAMINATION; ELECTROPHORESIS; GENES; HEAVY METALS; IRON; MOUNTAINS; PROTEINS

Citation Formats

Baker-Austin, C., M. Dopson, M. Wexler, R. G. Sawers, A. Stemmler, B.P. Rosen and P.L. Bond. Extreme arsenic resistance by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1. United States: N. p., 2007. Web. doi:10.1007/s00792-006-0052-z.
Baker-Austin, C., M. Dopson, M. Wexler, R. G. Sawers, A. Stemmler, B.P. Rosen and P.L. Bond. Extreme arsenic resistance by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1. United States. doi:10.1007/s00792-006-0052-z.
Baker-Austin, C., M. Dopson, M. Wexler, R. G. Sawers, A. Stemmler, B.P. Rosen and P.L. Bond. Mon . "Extreme arsenic resistance by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1". United States. doi:10.1007/s00792-006-0052-z.
@article{osti_908667,
title = {Extreme arsenic resistance by the acidophilic archaeon 'Ferroplasma acidarmanus' Fer1},
author = {Baker-Austin, C., M. Dopson, M. Wexler, R. G. Sawers, A. Stemmler, B.P. Rosen and P.L. Bond},
abstractNote = {'Ferroplasma acidarmanus' Fer1 is an arsenic-hypertolerant acidophilic archaeon isolated from the Iron Mountain mine, California; a site characterized by heavy metals contamination. The presence of up to 10 g arsenate per litre [As(V); 133 mM] did not significantly reduce growth yields, whereas between 5 and 10 g arsenite per litre [As(III); 67-133 mM] significantly reduced the yield. Previous bioinformatic analysis indicates that 'F. acidarmanus' Fer1 has only two predicted genes involved in arsenic resistance and lacks a recognizable gene for an arsenate reductase. Biochemical analysis suggests that 'F. acidarmanus' Fer1 does not reduce arsenate indicating that 'F. acidarmanus' Fer1 has an alternative resistance mechanism to arsenate other than reduction to arsenite and efflux. Primer extension analysis of the putative ars transcriptional regulator (arsR) and efflux pump (arsB) demonstrated that these genes are co-transcribed, and expressed in response to arsenite, but not arsenate. Two-dimensional polyacrylamide gel electrophoresis analysis of 'F. acidarmanus' Fer1 cells exposed to arsenite revealed enhanced expression of proteins associated with protein refolding, including the thermosome Group II HSP60 family chaperonin and HSP70 DnaK type heat shock proteins. This report represents the first molecular and proteomic study of arsenic resistance in an acidophilic archaeon.},
doi = {10.1007/s00792-006-0052-z},
journal = {Extremophiles},
number = ,
volume = 11,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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