Figure 7.

Schematic representation of glucose-mediated regulation of Mn²⁺transport.Left: T-bar and arrow indicate inhibition and activation of gene expression, respectively. Dotted arrow and T-bar indicate indirect effects. Proteins in red and blue represent Mn²⁺ importer and exporter, respectively. The arrow width in the transporter indicates putative overall effects of glucose on transporter genes expression. Direction of arrows indicates ion influx or efflux. Right: overall glucose-mediated effects of upshift of cellular Mn²⁺ equilibrium is shown. YwlE is a protein arginine phosphatase, which counteracts the arginine phosphorylation of proteins by McsB kinase, leading to protection of the protein from degradation including glycolytic enzymes. Glucose addition results in upshift of central carbon flow including glycolysis, tricarbonic acid cycle, and respiratory chain, leading to generation of toxic reactive oxygen species (ROS). Addition of glucose will increase the demand for superoxide dismutase (SOD).