Control of central metabolism's architecture in Escherichia coli: An overview.

Understanding metabolic networks' architecture is central to successfully manipulating metabolic fluxes in microbial cell factories. The transition of central metabolism's architecture from acetogenic to gluconeogenic and from the canonical monocyclic architecture of the Krebs tricarboxylic acids (TCA) cycle to a bicyclic architecture in which the TCA and the dicarboxylic acids (DCA) cycles work in unison, with the glyoxylate bypass fulfilling the anaplerotic function, has been the subject of much debate and remains elusive. In this article, the author sheds light on the intricacies surrounding the transition of central metabolism from one architecture to another and shows that the transition from the monocyclic architecture to the bicyclic architecture is triggered in response to a minimum threshold signal of growth rate (≲0.

Contrasting effects of isocitrate dehydrogenase deletion on fluxes through enzymes of central metabolism in Escherichia coli.

Flux analysis is central to understanding cellular metabolism and successful manipulation of metabolic fluxes in microbial cell-factories. Isocitrate dehydrogenase (ICDH) deletion conferred contrasting effects on fluxes through substrate-level phosphorylation (SLP) reactions. While significantly increasing flux through pyruvate kinase, it diminishes flux through succinyl CoA synthetase and upregulates phosphotransacetylase (PTA) and acetate kinase (AK).