@article{mbs:/content/journal/micro/10.1099/00221287-140-4-717, author = "Pronk, Jack T. and van der Linden-Beuman, Annelies and Verduyn, Cornelis and Scheffers, W. Alexander and van Dijken, Johannes P.", title = "Propionate metabolism in Saccharomyces cerevisiae: implications for the metabolon hypothesis", journal= "Microbiology", year = "1994", volume = "140", number = "4", pages = "717-722", doi = "https://doi.org/10.1099/00221287-140-4-717", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-140-4-717", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", keywords = "metabolic channelling", keywords = "Saccharomyces cerevisiae", keywords = "2-methylcitrate pathway", keywords = "propionate metabolism", abstract = "Aerobic, glucose-limited chemostat of Saccharomyces cerevisiae CBS 8066 cometabolized propionate when this compound was added to the reservoir medium. Co-metabolism of propionate led to an increase of the biomass and protein yields. Attempts to grow S. cerevisiae on propionate as a sole source of carbon and energy were not successful. Activities of propionyl-CoA synthetase in cell-free extracts were sufficient to account for the rates of propionate consumption observed in the chemostat cultures. Activities of propionyl-CoA carboxylase, a key enzyme of the methylmalonyl-CoA pathway of propionate metabolism, were negligible. In contrast, activities of 2-methylcitrate synthase, a key enzyme activity of the 2-methylcitrate pathway of propionate metabolism, increased substantially with increasing propionateto-glucose ratios in the reservoir media, and were sufficient to account for the propionate consumption rates observed in the chemostat cultures. This suggested that the 2-methylcitrate pathway is the major pathway of propionate metabolism in S. cerevisiae. In the literature, labelling patterns observed after incubation of this yeast with [3-13C]propionate have been interpreted as evidence for channelling of tricarboxylic acid (TCA) cycle intermediates, possibly as a consequence of the organization of TCA cycle enzymes in a metabolon. However, this interpretation of 13C-labelling patterns rested on the assumption that propionate metabolism in S. cerevisiae occurs via the methylmalonyl-CoA pathway. Since the distribution of 13C in alanine reported in the literature is fully compatible with a major role of the 2-methylcitrate pathway in propionate metabolism, it cannot be interpreted as evidence for the existence of a TCA cycle metabolon in S. cerevisiae. ", }