1.
Iron and sulfur oxidation pathways of Acidithiobacillus ferrooxidans.
Zhan, Y, Yang, M, Zhang, S, Zhao, D, Duan, J, Wang, W, Yan, L
World journal of microbiology & biotechnology. 2019;(4):60
Abstract
Acidithiobacillus ferrooxidans is a gram-negative, autotrophic and rod-shaped bacterium. It can gain energy through the oxidation of Fe(II) and reduced inorganic sulfur compounds for bacterial growth when oxygen is sufficient. It can be used for bio-leaching and bio-oxidation and contributes to the geobiochemical circulation of metal elements and nutrients in acid mine drainage environments. The iron and sulfur oxidation pathways of A. ferrooxidans play key roles in bacterial growth and survival under extreme circumstances. Here, the electrons transported through the thermodynamically favourable pathway for the reduction to H2O (downhill pathway) and against the redox potential gradient reduce to NAD(P)(H) (uphill pathway) during the oxidation of Fe(II) were reviewed, mainly including the electron transport carrier, relevant operon and regulation of its expression. Similar to the electron transfer pathway, the sulfur oxidation pathway of A. ferrooxidans, related genes and operons, sulfur oxidation mechanism and sulfur oxidase system are systematically discussed.
2.
Acidithiobacillus thiooxidans and its potential application.
Yang, L, Zhao, D, Yang, J, Wang, W, Chen, P, Zhang, S, Yan, L
Applied microbiology and biotechnology. 2019;(19):7819-7833
Abstract
Acidithiobacillus thiooxidans (A. thiooxidans) is a widespread, mesophilic, obligately aerobic, extremely acidophilic, rod-shaped, and chemolithoautotrophic gram-negative gammaproteobacterium. It can obtain energy and electrons from the oxidation of reducible sulfur, and it can fix carbon dioxide and assimilate nitrate, nitrite, and ammonium to satisfy carbon and nitrogen requirement. This bacterium exists as different genomovars and its genome size range from 3.02 to 3.97 Mb. Here, we highlight the recent advances in the understanding of the general biological features of A. thiooxidans, as well as the genetic diversity and the sulfur oxidation pathway system. Additionally, the potential applications of A. thiooxidans were summarized including the recycling of metals from metal-bearing ores, electric wastes, and sludge, the improvement of alkali-salinity soils, and the removal of sulfur from sulfur-containing solids and gases.