Stoichiometric modelling of ferric iron reduction in aerobic Acidithiobacillus thiooxidans DSM 17318 strain licanantay
The reduction of ferric ion under low dissolved oxygen concentrations and high loads of Fe (Ⅲ) has been considered an important industrial process and several studies have demonstrated that Acidithiobacillus ferrooxidans is able to reduce ferric ion (Fe(Ⅲ) ) under anaerobic conditions coupled to the oxidation of elemental sulfur and more recently aerobically with tetrathionate. In this work, based on previous genomic analysis and metabolic reconstruction of Acidithiobacillus thiooxidans DSM 17318 strain Licanantay, by flux balance analysis coupled to dynamic metabolic modelling, we report a remarkably high aerobic Fe(Ⅲ) reduction of 0. 147 mmol Fe(Ⅲ)/L-h, thirteen times higher than previously reported. This iron reduction is coupled to elemental sulfur oxidation in this strain which produces thiosulfate and its passive secretion to the extracellular space where it finally, in a non-enzymatical way, reduces Fe (Ⅲ). The application of this novel stoichiometric model enable us to estimate a thiosulfate efflux of 0. 064 mmol thiosulfate/g biomass ? h released to the extracellular space that can be coupled to accurately predict the reduction of Fe (Ⅲ) to ferrous ion, giving a quantitative metabolic detail of this important industrial bioleaching-related process.
strain Licanantay reduced inorganic sulphur compounds (RISCs) thiosulfate aerobic ferric reduction
Roberto A. Bobadilla Fazzini Pilar Parada
BioSigma S. A. Parque Industrial Los Libertadores, lote 106, Colina, Santiago de Chile, Chile
国际会议
The 19th International Biohydrometallurgy Symposium(第19届国际生物湿法冶金大会 IBS2011)
长沙
英文
215-219
2011-09-18(万方平台首次上网日期,不代表论文的发表时间)