Assimilation of Glucose and Related Compounds by Growing Cultures of Pseudomonas saccharophila

Abstract

In a study of the assimilation with different substrates by growing cultures of P. saccharophila, it has been shown that:[long dash]Whereas synthesis during growth with some substrates (glucose) is not greatly different from the "primary synthesis" shown by resting cell suspensions, with other substrates (lactate, pyruvate, and acetate) a rather great discrepancy appears between the results obtained in the 2 types of studies. With glucose as substrate, moderate variation in the temp. of incubation, the composition of the atmosphere, and the pH of the medium have no appreciable effect on the efficiency of assimilation. Complete removal of CO2 decreases synthesis, as do high concs. of oxygen. With very high partial pressures of O2 no growth occurs, although no effect of such atmospheres can be observed on the behavior of resting cell suspensions. An insufficiency of N does not materially affect the % of synthesis over a limited period of time, although it brings about a striking alteration in the composition of the organisms. An insufficiency of Fe in the medium esults in a decreased synthesis, particularly striking with those substrates utilized more rapidly than glucose. Pyruvic acid accumulates in iron-deficient media with sucrose and trehalose, but not with the other substrates studied as carbon sources.