Desulfovibrio electron transport

Function and Assembly of Electron-Transport Complexes in Desulfovibrio vulgaris Hildenborough... 

Badziog W,Thauer RK. 1980. Vectorial electron transport in Desulfovibrio vulgaris (Marburg) growing on hydrogen plus sulfate as sole energy source. Arch Microbiol 125 167-74. 

Mossbauer studies of the electron transport protein ferredoxin n from Desulfovibrio gigas have shown that the reduced Fe3S4 cluster contains one trapped valence Fe3+ site and one delocalized Fe2+-Fe3+ pair. The two Fe of the delocalized pair are indistinguishable, and the pair has a dimer spin S12 = 9/2, suggesting ferromagnetic coupling. 

In the photosynthetic and mitochondrial membranes the components of the transmembrane electron transport chain are not linked with covalent bonds, but fixed in a protein matrix. An example of such an arrangement of the electron transport chain in an artificial system can be found in papers by Tabushi et al. [244, 245], which deal with the dark electron transfer across the lipid membranes containing the dimers of cytochrome c3 from Desulfovibrio vulgaris. The dimer size is about 60 A, i.e. it somewhat exceeds the membrane thickness. This enables electron to move across the membrane via the cytochrome along the chain of hem fragments embedded in the protein. However, the characteristic time of the transmembrane electron transfer by this method is rather long (about 10 s). 

Thus, it is not necessary for this microorganism to carry out electron transport-coupled phosphorylation during growth with lactate and sulfate. This is in contrast to the sulfate-reducing bacteria belonging to the genus Desulfovibrio, which do not have the acetate, PP phosphotransferase, and therefore appear to have to carry out electron transport-coupled phosphorylation in order to obtain a net yield of ATP. 

Vosjan JH (1970) ATP generation by electron transport in Desulfovibrio desulfuricans. Antonie van Leeuwenhoek 36 584-586... 

The other side of the coin is the use of this electron transport chain in reverse when Desulfovibrio grows autotrophically on Ha gas, passing... 

---