Ferrous iron oxidation by sulfur-oxidizing Acidithiobacillus ferrooxidans and analysis of the process at the levels of transcription and protein synthesis

• Published in: Antonie van Leeuwenhoek 2013-04, Vol.103 (4), p.905-919
• Main Authors: Kucera, Jiri, Bouchal, Pavel, Lochman, Jan, Potesil, David, Janiczek, Oldrich, Zdrahal, Zbynek, Mandl, Martin
• Format: Article
• Language: English
• Subjects: Acidithiobacillus - growth & development; Acidithiobacillus - metabolism; Acidithiobacillus - physiology; Acidithiobacillus ferrooxidans; Adaptation, Physiological; Bacterial Proteins - biosynthesis; Bacteriology; Biomedical and Life Sciences; Electrophoresis, Gel, Two-Dimensional; Ferrous Compounds - metabolism; Gene Expression Profiling; Gene Expression Regulation; Iron; Iron - metabolism; Life Sciences; Medical Microbiology; Metabolic Networks and Pathways - genetics; Microbiology; Original Paper; Oxidation; Oxidation-Reduction; Plant Sciences; Polymerase chain reaction; Protein synthesis; Proteome - analysis; Proteomics; Pyrite; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Soil Science & Conservation; Sulfides - metabolism; Sulfur; Sulfur - metabolism; Transcription, Genetic
• ISSN: 0003-6072; 1572-9699
• DOI: 10.1007/s10482-012-9872-2

In contrast to iron-oxidizing Acidithiobacillus ferrooxidans, A. ferrooxidans from a stationary phase elemental sulfur-oxidizing culture exhibited a lag phase in pyrite oxidation, which is similar to its behaviour during ferrous iron oxidation. The ability of elemental sulfur-oxidizing A. ferrooxidans to immediately oxidize ferrous iron or pyrite without a lag phase was only observed in bacteria obtained from growing cultures with elemental sulfur. However, these cultures that shifted to ferrous iron oxidation showed a low rate of ferrous iron oxidation while no growth was observed. Two-dimensional gel electrophoresis was used for a quantitative proteomic analysis of the adaptation process when bacteria were switched from elemental sulfur to ferrous iron. A comparison of total cell lysates revealed 39 proteins whose increase or decrease in abundance was related to this phenotypic switching. However, only a few proteins were closely related to iron and sulfur metabolism. Reverse-transcription quantitative PCR was used to further characterize the bacterial adaptation process. The expression profiles of selected genes primarily involved in the ferrous iron oxidation indicated that phenotypic switching is a complex process that includes the activation of genes encoding a membrane protein, maturation proteins, electron transport proteins and their regulators.