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The role of acetogens in microbially influenced corrosion of steel.

Mand J, Park HS, Jack TR, Voordouw G - Front Microbiol (2014)

Bottom Line: Through a mechanism, that is still poorly understood, electrons or hydrogen (H2) molecules are removed from the metal surface and used as electron donor for sulfate reduction.The resulting ferrous ions precipitate in part with the sulfide produced, forming characteristic black iron sulfide.An extended MIC model capturing these results is presented.

View Article: PubMed Central - PubMed

Affiliation: Petroleum Microbiology Research Group, Department of Biological Sciences, University of Calgary Calgary, AB, Canada.

ABSTRACT
Microbially influenced corrosion (MIC) of iron (Fe(0)) by sulfate-reducing bacteria (SRB) has been studied extensively. Through a mechanism, that is still poorly understood, electrons or hydrogen (H2) molecules are removed from the metal surface and used as electron donor for sulfate reduction. The resulting ferrous ions precipitate in part with the sulfide produced, forming characteristic black iron sulfide. Hydrogenotrophic methanogens can also contribute to MIC. Incubation of pipeline water samples, containing bicarbonate and some sulfate, in serum bottles with steel coupons and a headspace of 10% (vol/vol) CO2 and 90% N2, indicated formation of acetate and methane. Incubation of these samples in serum bottles, containing medium with coupons and bicarbonate but no sulfate, also indicated that formation of acetate preceded the formation of methane. Microbial community analyses of these enrichments indicated the presence of Acetobacterium, as well as of hydrogenotrophic and acetotrophic methanogens. The formation of acetate by homoacetogens, such as Acetobacterium woodii from H2 (or Fe(0)) and CO2, is potentially important, because acetate is a required carbon source for many SRB growing with H2 and sulfate. A consortium of the SRB Desulfovibrio vulgaris Hildenborough and A. woodii was able to grow in defined medium with H2, CO2, and sulfate, because A. woodii provides the acetate, needed by D. vulgaris under these conditions. Likewise, general corrosion rates of metal coupons incubated with D. vulgaris in the presence of acetate or in the presence of A. woodii were higher than in the absence of acetate or A. woodii, respectively. An extended MIC model capturing these results is presented.

No MeSH data available.


Related in: MedlinePlus

Tree generated using UPGMA algorithm with distance between communities calculated using thetaYC coefficient in the Mothur software package. Tree was visualized with Mega. All field samples formed a tree separate from all enrichment samples. Water field samples were distinct from pipeline-associated samples.
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Figure 6: Tree generated using UPGMA algorithm with distance between communities calculated using thetaYC coefficient in the Mothur software package. Tree was visualized with Mega. All field samples formed a tree separate from all enrichment samples. Water field samples were distinct from pipeline-associated samples.

Mentions: Pyrosequencing of 16S rRNA amplicons for all seven field samples and for four coupon enrichment biofilms, gave 1357 to 6417 quality controlled reads for each sample (Table 2). The compositions of the microbial communities derived from these results are compared in Figure 6. Although the water samples were all from a single pipeline system, it is evident that the microbial communities in water samples retrieved along the flow path were distinct. The community of PW7 near the fresh water producing well-differed from those of PW8 and P0866, both further downstream and all of these were distinct from the communities at P0866S and P0848S downstream from the SBS injection point (Figures 1, 6). Microbial communities of PW8-PAS and PW8-PAW formed a separate branch in the dendrogram together with that of PW8. Communities in coupon enrichment biofilms differed significantly from those in field samples (Figure 6). Microbial communities formed following incubation with P0866, P0866S, and P0848S were very similar, whereas PW7 (Biofilm) was distinct from this cluster (Figure 6).


The role of acetogens in microbially influenced corrosion of steel.

Mand J, Park HS, Jack TR, Voordouw G - Front Microbiol (2014)

Tree generated using UPGMA algorithm with distance between communities calculated using thetaYC coefficient in the Mothur software package. Tree was visualized with Mega. All field samples formed a tree separate from all enrichment samples. Water field samples were distinct from pipeline-associated samples.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4043135&req=5

Figure 6: Tree generated using UPGMA algorithm with distance between communities calculated using thetaYC coefficient in the Mothur software package. Tree was visualized with Mega. All field samples formed a tree separate from all enrichment samples. Water field samples were distinct from pipeline-associated samples.
Mentions: Pyrosequencing of 16S rRNA amplicons for all seven field samples and for four coupon enrichment biofilms, gave 1357 to 6417 quality controlled reads for each sample (Table 2). The compositions of the microbial communities derived from these results are compared in Figure 6. Although the water samples were all from a single pipeline system, it is evident that the microbial communities in water samples retrieved along the flow path were distinct. The community of PW7 near the fresh water producing well-differed from those of PW8 and P0866, both further downstream and all of these were distinct from the communities at P0866S and P0848S downstream from the SBS injection point (Figures 1, 6). Microbial communities of PW8-PAS and PW8-PAW formed a separate branch in the dendrogram together with that of PW8. Communities in coupon enrichment biofilms differed significantly from those in field samples (Figure 6). Microbial communities formed following incubation with P0866, P0866S, and P0848S were very similar, whereas PW7 (Biofilm) was distinct from this cluster (Figure 6).

Bottom Line: Through a mechanism, that is still poorly understood, electrons or hydrogen (H2) molecules are removed from the metal surface and used as electron donor for sulfate reduction.The resulting ferrous ions precipitate in part with the sulfide produced, forming characteristic black iron sulfide.An extended MIC model capturing these results is presented.

View Article: PubMed Central - PubMed

Affiliation: Petroleum Microbiology Research Group, Department of Biological Sciences, University of Calgary Calgary, AB, Canada.

ABSTRACT
Microbially influenced corrosion (MIC) of iron (Fe(0)) by sulfate-reducing bacteria (SRB) has been studied extensively. Through a mechanism, that is still poorly understood, electrons or hydrogen (H2) molecules are removed from the metal surface and used as electron donor for sulfate reduction. The resulting ferrous ions precipitate in part with the sulfide produced, forming characteristic black iron sulfide. Hydrogenotrophic methanogens can also contribute to MIC. Incubation of pipeline water samples, containing bicarbonate and some sulfate, in serum bottles with steel coupons and a headspace of 10% (vol/vol) CO2 and 90% N2, indicated formation of acetate and methane. Incubation of these samples in serum bottles, containing medium with coupons and bicarbonate but no sulfate, also indicated that formation of acetate preceded the formation of methane. Microbial community analyses of these enrichments indicated the presence of Acetobacterium, as well as of hydrogenotrophic and acetotrophic methanogens. The formation of acetate by homoacetogens, such as Acetobacterium woodii from H2 (or Fe(0)) and CO2, is potentially important, because acetate is a required carbon source for many SRB growing with H2 and sulfate. A consortium of the SRB Desulfovibrio vulgaris Hildenborough and A. woodii was able to grow in defined medium with H2, CO2, and sulfate, because A. woodii provides the acetate, needed by D. vulgaris under these conditions. Likewise, general corrosion rates of metal coupons incubated with D. vulgaris in the presence of acetate or in the presence of A. woodii were higher than in the absence of acetate or A. woodii, respectively. An extended MIC model capturing these results is presented.

No MeSH data available.


Related in: MedlinePlus