Print Email Facebook Twitter Grow or store? Exploring metabolic decision making under feast/famine conditions using 13C tracer Title Grow or store? Exploring metabolic decision making under feast/famine conditions using 13C tracer Author Verhagen, K.J.A. (TU Delft OLD BT/Cell Systems Engineering) Gabriel Guedes da Silva, L. (TU Delft OLD BT/Cell Systems Engineering) van de Wijgaart, R. (TU Delft BT/Environmental Biotechnology) Kleerebezem, R. (TU Delft BT/Environmental Biotechnology) van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology) Wahl, S.A. (TU Delft OLD BT/Cell Systems Engineering) Date 2017-05-18 Abstract Natural habitats of microorganisms are dynamic environments with non-continuous supply of carbon and energy sources, in which intermediate storage of substrates can increase competitiveness. Plasticicumulans acidivorans are polyhydroxybutyrate (PHB) accumulating bacteria enriched from activated sludge using carbon feast-famine cycles as selective pressure. Despite growing slowly, P. acidivorans outcompetes other bacteria by quickly taking up acetate and storing it intracellularly as PHB to later use it for growth. As soon as acetate is depleted, these bacteria immediately ‘switch’ their metabolism from PHB production to consumption entailing a very interesting regulatory challenge as parallel activity could lead to significant losses (futile cycling). While the stoichiometry for both feast and famine phases has been extensively described in literature, the switch regulation is not yet fully understood. To elucidate the responsible regulatory processes, an enrichment of P. acidivorans was studied using targeted intracellular metabolite analysis over time, with emphasis on the feast to famine switch. In combination with extracellular rates, the measured intracellular metabolite pools are used to design a labelling experiment to obtain actual intracellular fluxes (dynamic 13C flux analysis). Here the challenge is to create an isotopically non-stationary state (usually mediated by changing the substrate’s isotopic composition) to study the metabolic response in the transition from presence-to-absence of substrate.In this way, we aim to unravel the responsible regulatory mechanism governing the metabolic switch from storage-to-consumption and use this knowledge not only to understand its ecological relevance, but to also propose novel metabolic strategies for microbial cell factory design. To reference this document use: http://resolver.tudelft.nl/uuid:11d242a9-e0de-465c-b44e-076250a9da53 Event Microbiological Methods for Waste & Water Resource Recovery 2017, 2017-05-18 → 2017-05-19, Delft, Netherlands Part of collection Institutional Repository Document type poster Rights © 2017 K.J.A. Verhagen, L. Gabriel Guedes da Silva, R. van de Wijgaart, R. Kleerebezem, Mark C.M. van Loosdrecht, S.A. Wahl Files PDF Grow_or_store.pdf 150.67 KB Close viewer /islandora/object/uuid:11d242a9-e0de-465c-b44e-076250a9da53/datastream/OBJ/view