PATHWAYS OF GLUCOSE OXIDATION IN DIVIDING AND NONDIVIDING CELLS OF ESCHERICHIA COLI

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Abstract
To judge the relative activity of the Embden-Meyerhof-Parnas pathway and a C-1 preferential pathway of glucose oxidation by growing populations of E. coli, a comparison of the amounts of labeled CO2 liberated by metabolism of glucose-1-C14 and glucose-6-C14 was made. Cultures were grown in a medium of inorganic salts and glucose in respirometer flasks. Analyses were also made for O2 uptake, evolution of CO2, utilization of glucose and ammonia-N and for number and length of cells. When glucose was the substrate that limited growth, the C-1: C-6 ratio dropped from 7.2 during the late logarithmic phase to 1.4 in the early stationary phase; with ammonia-N as the limiting substrate, the ratio was 4.9 in the late logarithmic phase and 2.1 in the early stationary phase. A test system to separate growth and cell division was devised; 1 to 3 [mu]g per ml of 5-diazouracil inhibited cell division but not growth. The metabolism of cultures was unaltered during the first 30 minutes of treatment. Both non-dividing and dividing cells growing at the same rate oxidized glucose primarily by a C-1 preferential pathway. The role of this pathway appears to be closely related to growth.