OBSERVATIONS ON A STRAIN OF NEISSERIA MENINGITIDIS IN THE PRESENCE OF GLUCOSE AND MALTOSE II

Abstract

When washed cells of N. meningitidis were suspended in phosphate buffer, and maltose was added to this system, inorganic phosphate was esterified. In contrast, in the presence of glucose, the concn. of inorganic phosphate did not change. The organism produced more acid from maltose than from glucose, although it did use glucose. Likewise, the rate of respiration in the presence of maltose was many times that of glucose when the cells were suspended in 0.018 [image] phosphate buffer. This difference in respiration was eliminated by the addition of L-glutamic acid and L-cystine. Respiration was greatly inhibited in the Krebs-Ringer phosphate soln. Respiration was increased, however, when the test mixtures were buffered with 3% CO2. The rates of respiration remained unaffected by addition of ATP. Iodoacetate lowered O2 consumption without affecting the anaerobic acid production. A selection of variants with an increased capacity to consume oxygen in the presence of either glucose or maltose occurred when the organism was transferred through chemically defined liquid media containing different concns. of inorganic phosphate and either of the 2 sugars. The result was not specific, i. e., cells that had been cultured in the presence of maltose and higher concns. of phosphate showed the greatest increase in respiration with glucose.