Anaerobic reduction of ethene to ethane in an enrichment culture

Abstract

A hydrogen-consuming methanogenic enrichment showed complete reduction of ethene to ethane. The ethene reduction was coupled to the formation of methane and addition of bromoethane sulfonate completely inhibited the reduction of ethene. At an ethene concentration of 0.8% in the gas phase (approximately 90 Wmol l 3I in the liquid phase), the formation of ethane from ethene was completely inhibited and methane formation was inhibited by 85%. Three dominant microorganisms were present in the enrichment. A highly motile, oval-shaped homoacetogenic bacterium, and two long, rod-shaped methanogens. One methanogen was irregularly crooked and the other one was Methanospirillum-like. The acetogen and the irregularly crooked methanogen were isolated, but in pure culture they did not reduce ethene. So far, we have been unable to isolate the other methanogen. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.

Abiotic dechlorination in rock matrices impacted by long-term exposure to TCE

“…Ethene can be an abiotic or biotic daughter product. It is also noted that ethane can be a biotic daughter product of ethene under anaerobic conditions, but this process is not common (de Bruin et al, 1992;Koene-Cottaar and Schraa, 1998;Schaefer et al, 2009Schaefer et al, , 2010. Furthermore, we have shown in our previous work using this rock type (Schaefer et al, 2013) that the rate of daughter product generation was not impacted by the presence of the microbial inhibitor mercuric chloride, which also is consistent with abiotic degradation processes.…”

Effects of ferrous iron supplementation on reductive dechlorination of tetrachloroethene and on methanogenic microbial community

“…Methanogens are thought to be involved in the reduction of ethene to ethane (De Bruin et al . 1992 ; Koene-Cottaar and Schraa 1998 ; Elsgaard 2013 ), although pure methanogenic cultures were not shown to reduce ethene (Koene-Cottaar and Schraa 1998 ). In the current study, any microorganisms’ increases were not strictly consistent with ethene reduction (Figs 2 and 6 ), and further research is needed to clarify the microorganisms associated with reduction of ethene to ethane.…”

Revisiting N2 fixation in Guerrero Negro intertidal microbial mats with a functional single-cell approach

“…This observed difference in the effect based on the applied assays could conceivably be caused by an enhanced consumption of ethylene, the measured product in ARAs, in molybdate-treated mats relative to un-amended controls. Ethylene can be metabolized aerobically ( de Bont, 1976 ), and anaerobically ( Koene-Cottaar and Schraa, 1998 ) by microorganisms, and especially the possibility of methanogens reducing ethylene ( Oremland, 1981 ; Elsgaard, 2013 ) should be mentioned in experiments where SRB are inhibited. Thus, enhanced ethylene consumption in the molybdate treatments could mistakenly be interpreted as a large contribution of SRB to N 2 fixation.…”