Database Retrieval System V1.0

Name doxD
Function
thiosulfate dehydrogenase (quinone) activity.
Definition thiosulfate dehydrogenase [quinone] large subunit [EC:1.8.5.2]
AA seq
MSGKQSEEFKRTEKMTRMEYLFPVRFAVGWMFLDGGLRKAVLKPAKLDPNSASFVGGKLV NFLPHAGPFKGLLLMTLENRSLDVTFLTVFSYIEIIAGLFIIIGLLTRLAALGALAMSVG FAPAYWLGSTCEDEWQIGALLTAGSVTLMLTAAGRVWGLDYFLYKKLGDRPIANVPILKW IKLW187
Structure
Reference
PMIDTitle & AuthorAbstractYear
028104963Insights from the docked DoxDA Model with Thiosulphate Sujay Ray , Angshuman Bagchi Redox reaction of inorganic sulphur compound is very essential to maintain a global sulphur cycle. Certain experimental evidences suggest that gamma-proteobacterial Acidothiobacillus thiooxidans; lacking the sulphur-oxidizing (sox) operon, has an alternative thiosulphate oxidation pathway. Dox operon having essentially participating proteins; DoxD and DoxA serves as the central players for this alternative pathway of thiosulphate oxidation. So, to identify their role in thiosulphate oxidation process, functional 3D model of DoxD and DoxA protein's independently functioning conserved domains were built after the contentment of necessary stereochemical features. After formation of the best suited DoxDA protein-complex, DoxDA was MD simulated in several steps and finally through MD simulation run utilizing GROMACS. Even after running beyond 20ns, 18ns simulated protein complex was the most stable and was selected for further study. Residual binding mode conferred mainly two ionic and twelve Hbonded interactions in DoxDA. Astonishingly, Asp167 and Arg18 from DoxA and DoxD, respectively was observed to hold a pivotal role in 6 H-bonds accompanied by a separate ionic interaction. Interestingly, four residues from DoxD; Trp32, Met33, Lys36 and Asn140 strengthened the DoxD-thiosulphate interaction. Interaction energy (deltaG = (-) 222.016kcal/mol) and net solvent accessibility calculations depicts spontaneous and fervent residual participation in DoxDA, which is essential for thiosulphate interaction and further sulphur oxidation. Conformational flexibility in DoxD with increased coil percentage benefits DoxD and makes its susceptible for the interaction with thiosulphate even after spontaneous interaction with DoxA. Therefore, this study serves as an insight at computational basis for sulphur oxidation even in organisms lacking sox operon.2016
117873067Regulation of a novel Acidithiobacillus caldus gene cluster involved in metabolism of reduced inorganic sulfur compounds Olena I Rzhepishevska , Jorge Valdés, Liucija Marcinkeviciene, Camelia Algora Gallardo, Rolandas Meskys, Violaine Bonnefoy, David S Holmes, Mark DopsonAcidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation.2007

Fabian H. Müller, Bandeiras T M , Urich T , et al. Coupling of the pathway of sulphur oxidation to dioxygen reduction: characterization of a novel membrane‐bound thiosulphate:quinone oxidoreductase[J]. Molecular Microbiology, 2004, 53(4):1147-1160. Purschke W G , Schmidt C L , Petersen A , et al. The terminal quinol oxidase of the hyperthermophilic archaeon Acidianus ambivalens exhibits a novel subunit structure and gene organization.[J]. Journal of Bacteriology, 1997, 179(4):1344-1353.