Sulfur Oxygenase Reductase (Sor) in the Moderately Thermoacidophilic Leaching Bacteria: Studies in Sulfobacillus thermosulfidooxidans and Acidithiobacillus caldus

Microorganisms

Claudia Janosch³  Francisco Remonsellez²  Wolfgang Sand³  Mario Vera³  Ricardo Amils¹ 

[1] Biofilm Centre, Aquatische Biotechnologie, Universität Duisburg-Essen, Universitätstraße 5, Essen, 45141, Germany;;Laboratorio de Tecnología de Membranas, Biotecnología y Medio Ambiente, Departamento de Ingeniería Química, Universidad Católica del Norte, Antofagasta 1270709, Chile; E-Mail:;Biofilm Centre, Aquatische Biotechnologie, Universität Duisburg-Essen, Universitätstraße 5, Essen, 45141, Germany; E-Mails:

关键词: Sulfobacillus thermosulfidooxidans;    Acidithiobacillus caldus;    sulfur metabolism;    sulfur oxygenase reductase;    genome;   

DOI  :  10.3390/microorganisms3040707

来源: mdpi

【 摘 要 】

The sulfur oxygenase reductase (Sor) catalyzes the oxygen dependent disproportionation of elemental sulfur, producing sulfite, thiosulfate and sulfide. Being considered an “archaeal like” enzyme, it is also encoded in the genomes of some acidophilic leaching bacteria such as Acidithiobacillus caldus, Acidithiobacillus thiooxidans, Acidithiobacillus ferrivorans and Sulfobacillus thermosulfidooxidans, among others. We measured Sor activity in crude extracts from Sb. thermosulfidooxidans DSM 9293^T. The optimum temperature for its oxygenase activity was achieved at 75 °C, confirming the “thermophilic” nature of this enzyme. Additionally, a search for genes probably involved in sulfur metabolism in the genome sequence of Sb. thermosulfidooxidans DSM 9293^T was done. Interestingly, no sox genes were found. Two sor genes, a complete heterodisulfidereductase (hdr) gene cluster, three tetrathionate hydrolase (tth) genes, three sulfide quinonereductase (sqr), as well as the doxD component of a thiosulfate quinonereductase (tqo) were found. Seven At. caldus strains were tested for Sor activity, which was not detected in any of them. We provide evidence that an earlier reported Sor activity from At. caldus S1 and S2 strains most likely was due to the presence of a Sulfobacillus contaminant.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.