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Accueil > Publications > Recherche par années > Années 1990 > 1994

Tholozan, JL ; Grivet, JP ; Vallet, C

Metabolic pathway to propionate of pectinatus-frisingensis, a strictly anaerobic beer-spoilage bacterium

Archives of Microbiology 162 (6) 401-408

par Administrateur - publié le

Abstract :

Pectinatus frisingensis, a recently described species of anaerobic mesophilic beer-spoilage bacteria, grows by fermenting various organic compounds, and produces mainly propionate, acetate, and succinate. Although acrylate and succinate were both dismutated by dense resting-cell suspensions, propionate production proceeded through the succinate pathway : [3-C-13]pyruvate consumption led to equal C-13-labeling of propionate on methyl and methylene groups. Growth on glucose or glycerol led to a similar propionate to acetate ratio, suggesting dihydroxyacetone phosphate as being a common metabolic intermediate. Diacetyl, 1,3-propanediol, and 2,3-butanediol were not growth substrates or fermentation products, but they were all dismutated by dense resting-cell suspensions to acetate and propionate. Acetoin was a minor fermentation product. The consumption of [2-C-13] or [3-C-13]pyruvate by dense resting-cell suspensions demonstrated the involvement of two equivalent pyruvate molecules during acetoin production. Key enzymes involved in this metabolism were measured in anoxic cell-free extracts. A tentative metabolic pathway to the main fermentation products was proposed from the above results.