Systematic alteration of in vitro metabolic environments reveals empirical growth relationships in cancer cell phenotypes.

Cancer cells, like microbes, live in complex metabolic environments. Recent evidence suggests that microbial behavior across metabolic environments is well described by simple empirical growth relationships, or growth laws. Do such empirical growth relationships also exist in cancer cells? To test this question, we develop a high-throughput approach to extract quantitative measurements of cancer cell behaviors in systematically altered metabolic environments.

Quorum Sensing and Metabolic State of the Host Control Lysogeny-Lysis Switch of Bacteriophage T1.

Bacterial viruses, or bacteriophages, are highly abundant in the biosphere and have a major impact on microbial populations. Many examples of phage interactions with their hosts, including establishment of dormant lysogenic and active lytic states, have been characterized at the level of the individual cell. However, much less is known about the dependence of these interactions on host metabolism and signal exchange within bacterial communities.

CRISPRi-Based Downregulation of Transcriptional Feedback Improves Growth and Metabolism of Arginine Overproducing .

Removing transcriptional feedback regulation of metabolic pathways is a classical approach to enhance overproduction of chemicals in microbes. However, disrupting transcriptional regulation can have broad physiological consequences that decrease cellular growth and productivity. Here, we compared downregulation and deletion of the transcriptional repressor ArgR in arginine overproducing .

Allosteric Feedback Inhibition Enables Robust Amino Acid Biosynthesis in E. coli by Enforcing Enzyme Overabundance.

Microbes must ensure robust amino acid metabolism in the face of external and internal perturbations. This robustness is thought to emerge from regulatory interactions in metabolic and genetic networks. Here, we explored the consequences of removing allosteric feedback inhibition in seven amino acid biosynthesis pathways in Escherichia coli (arginine, histidine, tryptophan, leucine, isoleucine, threonine, and proline).

Crosstalk between transcription and metabolism: how much enzyme is enough for a cell?

Cells employ various mechanisms for dynamic control of enzyme expression. An important mechanism is mutual feedback-or crosstalk-between transcription and metabolism. As recently suggested, enzyme levels are often much higher than absolutely needed to maintain metabolic flux.

Time-Optimized Isotope Ratio LC-MS/MS for High-Throughput Quantification of Primary Metabolites.

Cellular metabolite concentrations hold information on the function and regulation of metabolic networks. However, current methods to measure metabolites are either low-throughput or not quantitative. Here we optimized conditions for liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) for quantitative measurements of primary metabolites in 2 min runs.