Introduction Microbial cells secrete many metabolites during growth, including important intermediates of the central carbon
metabolism. This has not been taken into account by researchers when modeling microbial metabolism for metabolic
engineering and systems biology studies.
Materials and Methods The uptake of metabolites by microorganisms is well studied, but our knowledge of how and why
they secrete different intracellular compounds is poor. The secretion of metabolites by microbial cells has traditionally been
regarded as a consequence of intracellular metabolic overflow.
Conclusions Here, we provide evidence based on time-series metabolomics data that microbial cells eliminate some metabolites
in response to environmental cues, independent of metabolic overflow. Moreover, we review the different mechanisms
of metabolite secretion and explore how this knowledge can benefit metabolic modeling and engineering.The authors are thankful to Mia Jullig for assistance with Fig. 2. Callaghan Innovation and Bioresource Processing Alliance provided PhD stipends for James Daniell and Ninna Granucci respectively.info:eu-repo/semantics/publishedVersio
