Oxidation of Carbohydrates and Polyhydric Alcohols by Luminous Bacteria

Abstract

A comparative study of the oxidation of single substrates by the “resting” cells of the marine (Achromobacter fischeri) and the fresh water (Vibrio phosphorescens) luminous bacteria has revealed considerable difference in the ability of the 2 species to oxidize various carbohydrates and polyhydric alcohols. The rates of aerobic oxidation of 28 substrates by “resting” cells, prepared by washing thoroughly in the centrifuge and resuspending in phosphate buffer, were followed over a period of 3 hours in Warburg respirometers. The suspensions were adjusted to approximately the same density by means of a photronic cell turbiditimeter. The concentration of all substrates was M/60.

Although the per cent increase in oxygen uptake of the suspensions with substrate as compared with similar ones without the addition of substrate varied in some cases to a fairly wide degree, the ratio of the oxygen consumption with a given substrate to that with dextrose as a standard generally agreed to within less than 10% in repeated experiments. The controls, without added substrate, agreed with vessels containing substrates that were not oxidized to within 5% in the case of Vibrio phosphorescens though the agreement was not as close in the case of Achromobacter fischeri, in which the endogenous O₂ uptake was quite small and difficult to measure accurately.

The results are summarized in Table I. It is difficult to find any important correlations between the molecular configuration of the substrate and the ability of the organism to oxidize it. From the work that has been carried out thus far, however, it would seem that the primary limiting factor in both species is the number of carbon atoms, since only those compounds having 3 or 6 carbons are utilized. In the case of the disaccharides, those with beta linkages apparently are not utilized, while those with alpha linkages may or may not be utilized, irrespective of whether they are reducing sugars.