(Conversion of acetic acid to methane by thermophiles: Progress report)

Technical Report · Tue Jan 01 04:00:00 EST 1991

DOI:https://doi.org/10.2172/5680930· OSTI ID:5680930

Zinder, S

The objective of this project is to provide an understanding of thermophilic anaerobic microorganisms capable of breaking down acetic acid, the precursor of two-thirds of the methane produced by anaerobic bioreactors. Recent results include: (1) the isolation of Methanothrix strain CALLS-1, which grows much more rapidly than mesophilic strains; (2) the demonstration that thermophilic cultures of Methanosarcina and Methanothrix show minimum thresholds for acetate utilization of 1--2.5 mM and 10--20{mu}m respectively, in agreement with ecological data indicating that Methanothrix is favored by low acetate concentration; (3) the demonstration of high levels of thermostable acetyl-coA synthetase and carbon monoxide dehydrogenase in cell-free extracts of Methanothrix strains CALS-1; (4) the demonstration of methanogenesis from acetate and ATP in cell free extracts of strain CALS-1. (5) the demonstration that methanogenesis from acetate required 2 ATP/methane, and, in contrast to Methanosarcina, was independent of hydrogen and other electron donors; (6) the finding that entropy effects must be considered when predicting the level of hydrogen in thermophilic syntrophic cultures. (7) the isolation and characterization of the Desulfotomaculum thermoacetoxidans. Current research is centered on factors which allow thermophilic Methanothrix to compete with Methanosarcina.

• Research Organization: Cornell Univ., Ithaca, NY (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-85ER13370
• OSTI ID: 5680930
• Report Number(s): DOE/ER/13370-T1; ON: DE92010652
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090900 -- Biomass Fuels-- Processing-- (1990-)
550500 -- Metabolism
550700* -- Microbiology
59 BASIC BIOLOGICAL SCIENCES
ACETIC ACID
ACID ANHYDRASES
ALKANES
ANAEROBIC CONDITIONS
ATP-ASE
BACTERIA
BIOCONVERSION
BIOREACTORS
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CELL MEMBRANES
CHALCOGENIDES
DOCUMENT TYPES
ELEMENTS
ENZYMES
HYDROCARBONS
HYDROGEN
HYDROLASES
MEMBRANES
METABOLISM
METHANE
METHANOGENIC BACTERIA
MICROORGANISMS
MONOCARBOXYLIC ACIDS
NONMETALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXIDOREDUCTASES
OXYGEN COMPOUNDS
PHOSPHOHYDROLASES
PROGRESS REPORT
PROTEINS