title: Effect of decreasing growth temperature on cell yield of Escherichia coli.
abstract: Studies of the relationship between yield coefficient and growth rate, as affected by temperature of growth, in Escherichia coli have shown that, over a wide range of temperature, yield is relatively constant until the specific growth rate falls below about 0.2 hr(-1), at which point the yield begins to fall off precipitously. No intermediates of glucose metabolism in a form utilizable at higher temperatures could be found in the medium, and no toxic product was produced which limited growth. At 10 C, 37% of the carbon from glucose-UL-(14)C was assimilated into cellular material, whereas, at 30 C, 53% was assimilated. Cells grown at 10 C contained more carbohydrate than did cells grown at 37 C, and the glycogen-to-protein ratio of cells grown at 10 C was approximately three times higher than that of cells grown at 37 C. Adenosine triphosphatase activities of cells grown at 10 and 35 C were similar. Growth rates on glucose, glycerol, and succinate were quite similar at 10 C, but at 35 C growth was most rapid on glucose and slowest on succinate. The data suggest that the decrease in yield with decrease in temperature is a result of uncoupling of energy production from energy utilization.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D050260:Carbohydrate Metabolism; D002247:Carbon Isotopes; D004926:Escherichia coli / Q000254:growth & development* / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D010101:Oxygen Consumption; D013386:Succinates / Q000378:metabolism; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D002247:Carbon Isotopes; D013386:Succinates; D000251:Adenosine Triphosphatases; D005947:Glucose; D005990:Glycerol