Reconstitution of iron oxidase from sulfur-grown Acidithiobacillus ferrooxidans.
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ABSTRACT:
SUBMITTER: Taha TM
PROVIDER: S-EPMC2576702 | biostudies-literature | 2008 Nov
REPOSITORIES: biostudies-literature
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Reconstitution of iron oxidase from sulfur-grown Acidithiobacillus ferrooxidans.
Taha Taher M TM Kanao Tadayoshi T Takeuchi Fumiaki F Sugio Tsuyoshi T
Applied and environmental microbiology 20080912 21
The iron oxidation system from sulfur-grown Acidithiobacillus ferrooxidans ATCC 23270 cells was reconstituted in vitro. Purified rusticyanin, cytochrome c, and aa(3)-type cytochrome oxidase were essential for reconstitution. The iron-oxidizing activity of the reconstituted system was 3.3-fold higher than that of the cell extract from which these components were purified. ...[more]
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Project description:In this study, a proteomic analysis of Acidithiobacillus ferrooxidans by two-dimensional electrophoresis identified 24 proteins that were differentially expressed when the cells were grown on ferrous iron (Fe(2+)) or elemental sulfur (S°). Sixteen of these proteins were upregulated by growth on S° or downregulated by growth on Fe(2+), including four proteins involved in disulfide bond reduction such as pyridine nucleotide-disulfide oxidoreductase, heterodisulfide reductase subunit B, thioredoxin-disulfide reductase, and cysteine desulfurase IscS, and three proteins involved in saccharide metabolism. A total of eight proteins were upregulated by growth on Fe(2+) or downregulated by S°. Northern blots further confirmed the differences in transcription for these differentially expressed proteins. We functionally characterized cysteine desulfurase IscS, and found that its overexpression in E. coli promoted the growth of the cells in LB containing 2.5 % sodium thiosulfate. Our results provide new insights into the molecular basis for S° and Fe(2+) oxidation by this extreme acidophile.
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