Reciprocal Isomerization of Butyrate and Isobutyrate by the Strictly Anaerobic Bacterium Strain WoG13 and Methanogenic Isobutyrate Degradation by a Defined Triculture

AUTOR(ES)

Matthies, Carola

RESUMO

Isomerization of butyrate and isobutyrate was investigated with the recently isolated strictly anaerobic bacterium strain WoG13 which ferments glutarate to butyrate, isobutyrate, CO2, and small amounts of acetate. Dense cell suspensions converted butyrate to isobutyrate and isobutyrate to butyrate. 13C-nuclear magnetic resonance experiments proved that this isomerization was accomplished by migration of the carboxyl group to the adjacent carbon atom. In cell extracts, both butyrate and isobutyrate were activated to their coenzyme A (CoA) esters by acyl-CoA:acetate CoA-transferases. The reciprocal rearrangement of butyryl-CoA and isobutyryl-CoA was catalyzed by a butyryl-CoA:isobutyryl-CoA mutase which depended strictly on the presence of coenzyme B12. Isobutyrate was completely degraded via butyrate to acetate and methane by a defined triculture of strain WoG13, Syntrophomonas wolfei, and Methanospirillum hungatei.

Documentos Relacionados

• Thermophilic Anaerobic Degradation of Butyrate by a Butyrate-Utilizing Bacterium in Coculture and Triculture with Methanogenic Bacteria
• Effects of acetate, propionate, and butyrate on the thermophilic anaerobic degradation of propionate by methanogenic sludge and defined cultures.
• Anaerobic Degradation of Propionate by a Mesophilic Acetogenic Bacterium in Coculture and Triculture with Different Methanogens
• Kinetics of Butyrate, Acetate, and Hydrogen Metabolism in a Thermophilic, Anaerobic, Butyrate-Degrading Triculture
• Anaerobic Degradation of Normal- and Branched-Chain Fatty Acids with Four or More Carbons to Methane by a Syntrophic Methanogenic Triculture