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Microbial redox processes in deep subsurface environments and the potential application of (per)chlorate in oil reservoirs.

Liebensteiner MG, Tsesmetzis N, Stams AJ, Lomans BP - Front Microbiol (2014)

Bottom Line: Microbial reduction of (per)chlorate is a thermodynamically favorable redox process, also at high temperature.However, knowledge about (per)chlorate reduction at elevated temperatures is still scarce and restricted to members of the Firmicutes and the archaeon Archaeoglobus fulgidus.By analyzing the diversity and phylogenetic distribution of functional genes in (meta)genome databases and combining this knowledge with extrapolations to earlier-made physiological observations we speculate on the potential of (per)chlorate reduction in the subsurface and more precisely oil fields.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Microbiology, Wageningen University Wageningen, Netherlands.

ABSTRACT
The ability of microorganisms to thrive under oxygen-free conditions in subsurface environments relies on the enzymatic reduction of oxidized elements, such as sulfate, ferric iron, or CO2, coupled to the oxidation of inorganic or organic compounds. A broad phylogenetic and functional diversity of microorganisms from subsurface environments has been described using isolation-based and advanced molecular ecological techniques. The physiological groups reviewed here comprise iron-, manganese-, and nitrate-reducing microorganisms. In the context of recent findings also the potential of chlorate and perchlorate [jointly termed (per)chlorate] reduction in oil reservoirs will be discussed. Special attention is given to elevated temperatures that are predominant in the deep subsurface. Microbial reduction of (per)chlorate is a thermodynamically favorable redox process, also at high temperature. However, knowledge about (per)chlorate reduction at elevated temperatures is still scarce and restricted to members of the Firmicutes and the archaeon Archaeoglobus fulgidus. By analyzing the diversity and phylogenetic distribution of functional genes in (meta)genome databases and combining this knowledge with extrapolations to earlier-made physiological observations we speculate on the potential of (per)chlorate reduction in the subsurface and more precisely oil fields. In addition, the application of (per)chlorate for bioremediation, souring control, and microbial enhanced oil recovery are addressed.

No MeSH data available.


Related in: MedlinePlus

Diversity of catalytic subunits of selected DMSO Mo-enzymes. Protein sequences of characterized and functionally active enzymes and partial sequences retrieved from metagenomic datasets of oil reservoir environments are displayed; red circles mark the periplasmic location of the catalytic subunit, whereas green circles indicate activity with chlorate (next to the canonical enzyme function). For most of the DMSO enzymes no data are available regarding their activity towards perchlorate. Accession numbers and the respective microorganism/environment where the sequence derived from are indicated. The phylogenetic tree was constructed using the Neighbor-Joining method including bootstrap values (for 500 replicates). Evolutionary distances of the tree were computed using the Poisson correction method; bootstrap values above 70% are indicated by nodes at the respective branches. The scale bar indicates amino acid substitutions per site.
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Figure 2: Diversity of catalytic subunits of selected DMSO Mo-enzymes. Protein sequences of characterized and functionally active enzymes and partial sequences retrieved from metagenomic datasets of oil reservoir environments are displayed; red circles mark the periplasmic location of the catalytic subunit, whereas green circles indicate activity with chlorate (next to the canonical enzyme function). For most of the DMSO enzymes no data are available regarding their activity towards perchlorate. Accession numbers and the respective microorganism/environment where the sequence derived from are indicated. The phylogenetic tree was constructed using the Neighbor-Joining method including bootstrap values (for 500 replicates). Evolutionary distances of the tree were computed using the Poisson correction method; bootstrap values above 70% are indicated by nodes at the respective branches. The scale bar indicates amino acid substitutions per site.

Mentions: Several characterized molybdenum enzymes of the DMSO reductase family for instance (Figure 2) have shown to be rather unspecific in their substrate range. For some enzymes of this group the reduction of chlorate was demonstrated (besides the canonical function) in biochemical tests (Yamamoto et al., 1986; McEwan et al., 1987, 1991); especially Nar-type reductases seem to reduce chlorate at high rates (Moreno-Vivian et al., 1999; Afshar et al., 2001). The activity for enzymes of the DMSO family towards perchlorate has often not been assessed. An exception is the Nar-type enzyme of Marinobacter hydrocarbonoclasticus strain 617, which has a very low activity with perchlorate (Marangon et al., 2012).


Microbial redox processes in deep subsurface environments and the potential application of (per)chlorate in oil reservoirs.

Liebensteiner MG, Tsesmetzis N, Stams AJ, Lomans BP - Front Microbiol (2014)

Diversity of catalytic subunits of selected DMSO Mo-enzymes. Protein sequences of characterized and functionally active enzymes and partial sequences retrieved from metagenomic datasets of oil reservoir environments are displayed; red circles mark the periplasmic location of the catalytic subunit, whereas green circles indicate activity with chlorate (next to the canonical enzyme function). For most of the DMSO enzymes no data are available regarding their activity towards perchlorate. Accession numbers and the respective microorganism/environment where the sequence derived from are indicated. The phylogenetic tree was constructed using the Neighbor-Joining method including bootstrap values (for 500 replicates). Evolutionary distances of the tree were computed using the Poisson correction method; bootstrap values above 70% are indicated by nodes at the respective branches. The scale bar indicates amino acid substitutions per site.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150442&req=5

Figure 2: Diversity of catalytic subunits of selected DMSO Mo-enzymes. Protein sequences of characterized and functionally active enzymes and partial sequences retrieved from metagenomic datasets of oil reservoir environments are displayed; red circles mark the periplasmic location of the catalytic subunit, whereas green circles indicate activity with chlorate (next to the canonical enzyme function). For most of the DMSO enzymes no data are available regarding their activity towards perchlorate. Accession numbers and the respective microorganism/environment where the sequence derived from are indicated. The phylogenetic tree was constructed using the Neighbor-Joining method including bootstrap values (for 500 replicates). Evolutionary distances of the tree were computed using the Poisson correction method; bootstrap values above 70% are indicated by nodes at the respective branches. The scale bar indicates amino acid substitutions per site.
Mentions: Several characterized molybdenum enzymes of the DMSO reductase family for instance (Figure 2) have shown to be rather unspecific in their substrate range. For some enzymes of this group the reduction of chlorate was demonstrated (besides the canonical function) in biochemical tests (Yamamoto et al., 1986; McEwan et al., 1987, 1991); especially Nar-type reductases seem to reduce chlorate at high rates (Moreno-Vivian et al., 1999; Afshar et al., 2001). The activity for enzymes of the DMSO family towards perchlorate has often not been assessed. An exception is the Nar-type enzyme of Marinobacter hydrocarbonoclasticus strain 617, which has a very low activity with perchlorate (Marangon et al., 2012).

Bottom Line: Microbial reduction of (per)chlorate is a thermodynamically favorable redox process, also at high temperature.However, knowledge about (per)chlorate reduction at elevated temperatures is still scarce and restricted to members of the Firmicutes and the archaeon Archaeoglobus fulgidus.By analyzing the diversity and phylogenetic distribution of functional genes in (meta)genome databases and combining this knowledge with extrapolations to earlier-made physiological observations we speculate on the potential of (per)chlorate reduction in the subsurface and more precisely oil fields.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Microbiology, Wageningen University Wageningen, Netherlands.

ABSTRACT
The ability of microorganisms to thrive under oxygen-free conditions in subsurface environments relies on the enzymatic reduction of oxidized elements, such as sulfate, ferric iron, or CO2, coupled to the oxidation of inorganic or organic compounds. A broad phylogenetic and functional diversity of microorganisms from subsurface environments has been described using isolation-based and advanced molecular ecological techniques. The physiological groups reviewed here comprise iron-, manganese-, and nitrate-reducing microorganisms. In the context of recent findings also the potential of chlorate and perchlorate [jointly termed (per)chlorate] reduction in oil reservoirs will be discussed. Special attention is given to elevated temperatures that are predominant in the deep subsurface. Microbial reduction of (per)chlorate is a thermodynamically favorable redox process, also at high temperature. However, knowledge about (per)chlorate reduction at elevated temperatures is still scarce and restricted to members of the Firmicutes and the archaeon Archaeoglobus fulgidus. By analyzing the diversity and phylogenetic distribution of functional genes in (meta)genome databases and combining this knowledge with extrapolations to earlier-made physiological observations we speculate on the potential of (per)chlorate reduction in the subsurface and more precisely oil fields. In addition, the application of (per)chlorate for bioremediation, souring control, and microbial enhanced oil recovery are addressed.

No MeSH data available.


Related in: MedlinePlus