Sulphate reducing bacteria (SRB) are a specialized group of microorganisms that use sulphate as terminal electron acceptor for their respiration. Desulfovibrio gigas, a mesophilic Gram-negative curved rod bacterium from the d-subgroup of proteobacteria is a member of the Desulfovibrio genus, which has been one of the most studied organisms of the SRB. As energy source, Desulfovibrio sp. can generally use organic acids, alcohols and molecular hydrogen for sulphate reduction.

 

These bacteria have a wide biotechnology potential. For example, sewage and several types of industrial waste liquids can be treated by microbiological purification processes prior to release into the environment. Furthermore SRBs can also participate in interspecies hydrogen transfer leading to methanogenesis processes. However, SRBs can cause economical problems due to corrosion of pipelines in anaerobic environments like offshore oil production or watterlogged clay soils, mainly caused by hydrogenase activity.

 

Until recently there was a tremendous lack of genetic and molecular biology approaches on D. gigas. We have implemented many of these approaches and as well as we have constructed several mutants such as in genes encoding Rubredoxin Oxygen Oxidoreductase, ROO, the hydrogenase Ech-like, from a membrane-bound [NiFe] hydrogenase, and the flavoredoxin, respectively.