Currently, the application of next-generation sequencing methods of DNA in
studies of metagenomic and metatranscriptomic has revealed the existence of novel
sulfate reducers not yet cultivated in different environments, mainly marine habitats,
and they are classified in others lineages to those already known (Anantharaman
et al. 2018). Therefore, the knowledge of phylogenetic relationships of this particular
microbial group allows a better understanding of their energy and nutritional
demands, as well as a perception of their way of life in a given environment, and
their possible biotechnological application.
13.4.2 Biotechnological Implications
Biotechnology offers an alternative to develop and to innovate methods using as
tools the knowledge biochemistry and the organism’s manipulation, with the goal of
obtaining valuable products or improving an industrial process while maintaining
the natural environment. In this sense, environmental pollution and waste treatment
are mainly treated by microorganisms (Mani and Kumar 2014). In this way, SRB
have great implications in the context of environmental biotechnology.
Sulfate-reducing bacteria can cause serious problems for industries, the production of sulfide, a highly reactive and corrosive compound, provoking corrosion of
iron and steel, which affects mainly to oil, hydroelectric and metal-mechanic industry (Gadd 2010; Hernández-Gayoso et al. 2004). Metallic corrosion is one of the
main damages causing great economic losses in pipeline systems of the petroleum
industry. In particular, D. desulfuricans, D. vulgaris, D. vietnamensis and
D. alaskensis play an important role in the biocorrosion of metallic surfaces due to
H 2 S production, which modifies the environmental pH and leads to the formation of
the corrosion product FeS. SRB also promote the development of biofilms in aquatic
environments, which are associated with located corrosion of the metal surfaces of
oil pipelines. The production of hydrogen sulfide by SRB sours oil and gas; this
reduces the quality and the cost of them (Dinh et al. 2004; Muyzer and Stams 2008:
Neria-González et al. 2006). Also, SRB have health implications since some species
of Desulfovibrio can act as opportunistic pathogens; they are associated with primary
bacteremia and abdominal infections, such as abscesses and cholecystitis (Urata
et al. 2008).
Due to the demand of sulfuric acid on the manufacture of fertilizer and its use in
applications in oil refining, pigment production, steel treatment and non-ferrous
metal extraction and manufacture of explosives, detergents, plastics and fibres, it
results in the occurrence of sulfate in wastewater. The presence of sulfate has an
impact on the biological treatment in the wastewaters. In nature, sulfate reducers
coexist with other microorganisms, which drifts in metabolic interactions, i.e. the
sulfate reducers compete with the methanogens and acetogens for common
substrates, such as hydrogen and acetate, but in the absence of sulfate, sulfate
reducers grow acetogenically in syntrophic with the methanogens. These microbial
interactions are important in the treatment of wastewater. The heavy metals are other
pollutants very common of the wastewater; its presence is a very serious threat to the
13 Heavy Metal Removal Processes by Sulfate-Reducing Bacteria
377
studies of metagenomic and metatranscriptomic has revealed the existence of novel
sulfate reducers not yet cultivated in different environments, mainly marine habitats,
and they are classified in others lineages to those already known (Anantharaman
et al. 2018). Therefore, the knowledge of phylogenetic relationships of this particular
microbial group allows a better understanding of their energy and nutritional
demands, as well as a perception of their way of life in a given environment, and
their possible biotechnological application.
13.4.2 Biotechnological Implications
Biotechnology offers an alternative to develop and to innovate methods using as
tools the knowledge biochemistry and the organism’s manipulation, with the goal of
obtaining valuable products or improving an industrial process while maintaining
the natural environment. In this sense, environmental pollution and waste treatment
are mainly treated by microorganisms (Mani and Kumar 2014). In this way, SRB
have great implications in the context of environmental biotechnology.
Sulfate-reducing bacteria can cause serious problems for industries, the production of sulfide, a highly reactive and corrosive compound, provoking corrosion of
iron and steel, which affects mainly to oil, hydroelectric and metal-mechanic industry (Gadd 2010; Hernández-Gayoso et al. 2004). Metallic corrosion is one of the
main damages causing great economic losses in pipeline systems of the petroleum
industry. In particular, D. desulfuricans, D. vulgaris, D. vietnamensis and
D. alaskensis play an important role in the biocorrosion of metallic surfaces due to
H 2 S production, which modifies the environmental pH and leads to the formation of
the corrosion product FeS. SRB also promote the development of biofilms in aquatic
environments, which are associated with located corrosion of the metal surfaces of
oil pipelines. The production of hydrogen sulfide by SRB sours oil and gas; this
reduces the quality and the cost of them (Dinh et al. 2004; Muyzer and Stams 2008:
Neria-González et al. 2006). Also, SRB have health implications since some species
of Desulfovibrio can act as opportunistic pathogens; they are associated with primary
bacteremia and abdominal infections, such as abscesses and cholecystitis (Urata
et al. 2008).
Due to the demand of sulfuric acid on the manufacture of fertilizer and its use in
applications in oil refining, pigment production, steel treatment and non-ferrous
metal extraction and manufacture of explosives, detergents, plastics and fibres, it
results in the occurrence of sulfate in wastewater. The presence of sulfate has an
impact on the biological treatment in the wastewaters. In nature, sulfate reducers
coexist with other microorganisms, which drifts in metabolic interactions, i.e. the
sulfate reducers compete with the methanogens and acetogens for common
substrates, such as hydrogen and acetate, but in the absence of sulfate, sulfate
reducers grow acetogenically in syntrophic with the methanogens. These microbial
interactions are important in the treatment of wastewater. The heavy metals are other
pollutants very common of the wastewater; its presence is a very serious threat to the
13 Heavy Metal Removal Processes by Sulfate-Reducing Bacteria
377