Effect of specific growth rate and glucose concentration on growth and glucose metabolism of Escherichia coli K-12.
Chemostat cultures of E. coli K-12 revealed that the metabolic change from respiration to aerobic fermentation can be obtained with increasing specific growth rate at low glucose input concentration (0.1%), or increasing glucose input concentrations at low specific growth rate (0.1 h-1). Both effects do not affect biomass formation. The metabolic change is not related to a pathway switch of glucose utilization. The increase in specific growth rate causes suppression of succinate dehydrogenase, and NADH oxidase, whereas glucose increases cause suppression of succinate dehydrogenase, cytochrome a and 2-ketoglutarate dehydrogenase. Both phenomena are reflected in the specific oxygen uptake rate, specific carbon dioxide production rate and respiratory quotient values. Growth limitation could be related to a maximal glucose uptake rate of the cell and thus constitutes an entirely different effect caused by high glucose input concentration.
D000332:Aerobiosis; D002474:Cell-Free System; D003579:Cytochrome Reductases / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D007655:Ketoglutarate Dehydrogenase Complex / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010101:Oxygen Consumption; D013385:Succinate Dehydrogenase / Q000378:metabolism
D007655:Ketoglutarate Dehydrogenase Complex; D013385:Succinate Dehydrogenase; D009247:NADH, NADPH Oxidoreductases; D003579:Cytochrome Reductases; D005947:Glucose