Differential Protein Expression during Growth of Acidithiobacillus ferrooxidans on Ferrous Iron, Sulfur Compounds, or Metal Sulfides
AUTOR(ES)
Ramírez, Pablo
FONTE
American Society for Microbiology
RESUMO
A set of proteins that changed their levels of synthesis during growth of Acidithiobacillus ferrooxidans ATCC 19859 on metal sulfides, thiosulfate, elemental sulfur, and ferrous iron was characterized by using two-dimensional polyacrylamide gel electrophoresis. N-terminal amino acid sequencing and mass spectrometry analysis of these proteins allowed their identification and the localization of the corresponding genes in the available genomic sequence of A. ferrooxidans ATCC 23270. The genomic context around several of these genes suggests their involvement in the energetic metabolism of A. ferrooxidans. Two groups of proteins could be distinguished. The first consisted of proteins highly upregulated by growth on sulfur compounds (and downregulated by growth on ferrous iron): a 44-kDa outer membrane protein, an exported 21-kDa putative thiosulfate sulfur transferase protein, a 33-kDa putative thiosulfate/sulfate binding protein, a 45-kDa putative capsule polysaccharide export protein, and a putative 16-kDa protein of unknown function. The second group of proteins comprised those downregulated by growth on sulfur (and upregulated by growth on ferrous iron): rusticyanin, a cytochrome c552, a putative phosphate binding protein (PstS), the small and large subunits of ribulose biphosphate carboxylase, and a 30-kDa putative CbbQ protein, among others. The results suggest in general a separation of the iron and sulfur utilization pathways. Rusticyanin, in addition to being highly expressed on ferrous iron, was also newly synthesized, as determined by metabolic labeling, although at lower levels, during growth on sulfur compounds and iron-free metal sulfides. During growth on metal sulfides containing iron, such as pyrite and chalcopyrite, both proteins upregulated on ferrous iron and those upregulated on sulfur compounds were synthesized, indicating that the two energy-generating pathways are induced simultaneously depending on the kind and concentration of oxidizable substrates available.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=492426Documentos Relacionados
- An Exported Rhodanese-Like Protein Is Induced during Growth of Acidithiobacillus ferrooxidans in Metal Sulfides and Different Sulfur Compounds
- Ferrous Iron and Sulfur Oxidation and Ferric Iron Reduction Activities of Thiobacillus ferrooxidans Are Affected by Growth on Ferrous Iron, Sulfur, or a Sulfide Ore
- Selective Inhibition of the Oxidation of Ferrous Iron or Sulfur in Thiobacillus ferrooxidans
- Oxidation of Ferrous Iron and Elemental Sulfur by Thiobacillus ferrooxidans
- Identificação e caracterização de genes expressos diferencialmente em Acidithiobacillus ferrooxidans na presença de sulfetos metalicos