STUDIES ON THE OXIDATION OF GLUCOSE BY PSEUDOMONAS FLUORESCENS

Abstract

escent pseudomonads, grown in complex media containing a high concentration of glucose, will convert this sugar to gluconic acid and in some cases further to 2-ketogluconic acid, often with yields approximating 90 per cent of theory. These observations suggest that the metabolism of glucose by fluorescent pseu-domonads may involve a direct oxidative attack, rather than a degradation via the glycolytic pathway; but the evidence cited above cannot be considered as conclusive proof that oxidation via gluconic acid is the only pathway for the breakdown of glucose. The extremely high concentrations of glucose employed, (over 10 per cent) might well have caused a derangement of normal carbo-hydrate metabolism, and called into operation a shunt mechanism not functional, as a rule, to any appreciable extent. The following experiments were designed to investigate the nature of glucose metabolism by Pseudomonas fluorescens under more normal physiological conditions. METHODS P8eudomonas fluorescens, strain A, 3.12, was employed exclusively. Cultures