Hydrogen partial pressures in a thermophilic acetate-oxidizing methanogenic coculture. [THF, Methanobacterium thermoautotrophicum]

Journal Article · Wed Jun 01 04:00:00 EDT 1988 · Water Resources Research; (USA)

OSTI ID:5199474

Lee, M J; Zinder, S H ^[1]

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1. Cornell Univ., Ithaca, NY (USA)

Hydrogen partial pressures were measured in a thermophilic coculture comprised of a eubacterial rod which oxidized acetate to H{sub 2} and CO{sub 2} and a hydrogenotrophic methanogen, Methanobacterium sp. strain THF. H{sub 2} partial pressures in the coculture were measured to be between 20 and 50 Pa (0.12 to 0.30 {mu}M) during acetate utilization, approximately one order of magnitude higher than originally predicted by Zinder and Koch. However, when {Delta}G{sub f} (free energy of formation) values were corrected for 60{degree}C, the predicted value was near 15 Pa, in closer agreement with the experimentally determined values. The coculture also oxidized ethanol to acetate with H{sub 2} partial pressure values as high as 200 Pa. Acetate was not used until after the ethanol was consumed and the H{sub 2} partial pressure decreased to 40 to 50 Pa. After acetate utilization, H{sub 2} partial pressures fell to approximately 10 Pa and remained there, indicating a threshold for H{sub 2} utilization by the methanogen. Axenic cultures of the acetate-oxidizing organism were combined with pure cultures of either Methanobacterium sp. strain THF or Methanobacterium thermoautotrophicum {Delta}H to form reconstituted acetate-oxidizing cocultures. The H{sub 2} partial pressures measured in both of these reconstituted cocultures were similar to those measured in the original acetate-oxidizing rod coculture. Since M. thermoautotrophicum {Delta}H did not use formate as a substrate, formate is not necessarily involved in interspecies electron transfer in this coculture.

• OSTI ID: 5199474
• Journal Information: Water Resources Research; (USA), Journal Name: Water Resources Research; (USA) Vol. 54:6; ISSN 0043-1397; ISSN WRERA
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090900* -- Biomass Fuels-- Processing-- (1990-)
ACETATES
ALKANES
BACTERIA
BIODEGRADATION
BIOSYNTHESIS
CARBOXYLIC ACID SALTS
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
HYDROCARBONS
HYDROGEN
METHANE
METHANOGENIC BACTERIA
MICROORGANISMS
NONMETALS
ORGANIC COMPOUNDS
PARTIAL PRESSURE
SYNTHESIS
THERMOPHILIC CONDITIONS