Genetic control of enzyme activity drives metabolic adaptations to environmental changes, and therefore the feedback interaction between gene expression and metabolism is essential to cell fitness. In this paper we develop a new formalism to detect the equilibrium regimes of an unbranched metabolic network under transcriptional feedback from one metabolite. Our results indicate that one-to-all transcriptional feedback can induce a wide range of metabolic phenotypes, including mono-, multistability and oscillatory behavior. The analysis is based on the use of switch-like models for transcriptional control and the exploitation of the time scale separation between metabolic and genetic dynamics. For any combination of activation and repression feedback loops, we derive conditions for the emergence of a specific phenotype in terms of genetic parameters such as enzyme expression rates and regulatory thresholds. We find that metabolic oscillations can emerge under uniform thresholds and, in the case of operoncontrolled networks, the analysis reveals how nutrient-induced bistability and oscillations can emerge as a consequence of the transcriptional feedback.

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Gestaltung von Mensch-Technik-Schnittstellen für die Digitalisierung von Planungs-und Steuerungsprozessen auf Automobilterminals

In today’s buyer’s markets, logistical service quality is of great importance, particularly for high-priced products. For many buyers, the automobile is the epitome of a high-priced, individually customized product. Hence, customers expect a high delivery service quality. Distribution logistics provides the link between the manufacturer and the customer and is therefore responsible for providing these services. In automobile logistics, the distribution chain involves several stakeholders, such as manufacturers, transport, and technical services providers, as well as dealers. Seamless coordination between them is crucial. Digitalization is an inevitable means for gaining a high level of transparency among the stakeholders. In addition, it provides technologies for developing effective and tailor-made assistance and control systems that support processes along the distribution chain. In recent years, the BIBA—Bremer Institut für Produktion und Logistik GmbH has been active in automobile logistics research and has been involved in developing several assistant and control systems that range from relatively simple track and trace systems to highly complex compound control systems. In this paper, we present an overview of the developed systems and provide a vision, how recent and ongoing research improves automobile logistics and how to further potential can be leveraged.

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