title: Comparative proteomic analysis of sulfur-oxidizing Acidithiobacillus ferrooxidans CCM 4253 cultures having lost the ability to couple anaerobic elemental sulfur oxidation with ferric iron reduction.
abstract: In extremely acidic environments, ferric iron can be a thermodynamically favorable electron acceptor during elemental sulfur oxidation by some Acidithiobacillus spp. under anoxic conditions. Quantitative 2D-PAGE proteomic analysis of a resting cell suspension of a sulfur-grown Acidithiobacillus ferrooxidans CCM 4253 subculture that had lost its iron-reducing activity revealed 147 protein spots that were downregulated relative to an iron-reducing resting cell suspension of the antecedent sulfur-oxidizing culture and 111 that were upregulated. Tandem mass spectrometric analysis of strongly downregulated spots identified several physiologically important proteins that apparently play roles in ferrous iron oxidation, including the outer membrane cytochrome Cyc2 and rusticyanin. Other strongly repressed proteins were associated with sulfur metabolism, including heterodisulfide reductase, thiosulfate:quinone oxidoreductase and sulfide:quinone reductase. Transcript-level analyses revealed additional downregulation of other respiratory genes. Components of the iron-oxidizing system thus apparently play central roles in anaerobic sulfur oxidation coupled with ferric iron reduction in the studied microbial strain.
authors.affiliation: Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic. Electronic address: jiri.kucera@mail.muni.cz.
authors.forename: Jiri
authors.initials: J
authors.lastname: Kucera
authors.affiliation: Mendel Centre for Plant Genomics and Proteomics, Central European Technology Institute, Brno, Czech Republic. Electronic address: sedo@sci.muni.cz.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Sedo
authors.affiliation: Mendel Centre for Plant Genomics and Proteomics, Central European Technology Institute, Brno, Czech Republic. Electronic address: dpotesil@mail.muni.cz.
authors.forename: David
authors.initials: D
authors.lastname: Potesil
authors.affiliation: Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic. Electronic address: janiczek@chemi.muni.cz.
authors.forename: Oldrich
authors.initials: O
authors.lastname: Janiczek
authors.affiliation: Mendel Centre for Plant Genomics and Proteomics, Central European Technology Institute, Brno, Czech Republic. Electronic address: zdrahal@sci.muni.cz.
authors.forename: Zbynek
authors.initials: Z
authors.lastname: Zdrahal
authors.affiliation: Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic. Electronic address: mandl@chemi.muni.cz.
authors.forename: Martin
authors.initials: M
authors.lastname: Mandl
mesh_terms: D042763:Acidithiobacillus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000693:Anaerobiosis; D001426:Bacterial Proteins / Q000032:analysis*; D015180:Electrophoresis, Gel, Two-Dimensional; D020869:Gene Expression Profiling; D007501:Iron / Q000378:metabolism*; D009154:Mutation; D010084:Oxidation-Reduction; D020543:Proteome / Q000032:analysis*; D013455:Sulfur / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D020543:Proteome; D013455:Sulfur; D007501:Iron
keywords: Acidithiobacillus ferrooxidans; Anaerobic respiratory pathway; Ferric iron reduction; Proteomics; Sulfur metabolism