Amino acids are key substrates to Escherichia coli BW25113 for achieving high specific growth rate

Publication date: Available online 11 February 2020Source: Research in MicrobiologyAuthor(s): Andres Maser, Karl Peebo, Raivo Vilu, Ranno NahkuAbstractStudying substrate consumption in nutrient-rich conditions is challenging because often the growth medium includes undefined components like yeast extract or peptone. For clear and consistent results, it is necessary to use defined medium, where substrate utilization can be followed. In the present work, Escherichia coli BW25113 batch growth in a medium supplemented with 20 proteinogenic amino acids and glucose was studied. Focus was on the quantitative differences in substrate consumption and proteome composition between minimal and nutrient-rich medium. In the latter, 72% of carbon used for biomass growth came from amino acids and 28% from glucose. Serine was identified as the most consumed substrate with 41% of total carbon consumption. Proteome comparison between nutrient-rich and minimal medium revealed changes in TCA cycle and acetate producing enzymes that together with extracellular metabolite data pointed to serine being consumed mainly for energy generation purposes. Serine removal from the growth medium decreased specific growth rate by 22%. In addition, proteome comparison between media revealed a large shift in amino acid synthesis and translation related proteins. Overall, this work describes in quantitative terms the batch growth carbon uptake profile and proteome allocation of Escherichia coli BW25113 in minimal...
Source: Research in Microbiology - Category: Microbiology Source Type: research