The relationship between catabolism of glycerol and metabolism of hexosephosphate derivatives in Pseudomonas aeruginosa was studied by comparing the growth on glycerol and enzymatic constitution of strain PAO with these characteristics of glucose-catabolic mutants and revertants. Growth of strain PAO on glycerol induced a catabolic oxidized nicotinamide adenine dinucleotide-linked glyceraldehyde-phosphate dehydrogenase and seven glucose-catabolic enzymes. The results indicated that these enzymes were induced by a six-carbon metabolite of glucose. All strains possessed a constitutive anabolic Embden-Meyerhof-Parnas pathway allowing limited conversion of glycerol-derived triosephosphate to hexosephosphate derivatives, which was consistent with induction of these enzymes by glycerol. Phosphogluconate dehydratase-deficient mutants grew on glycerol. However, mutants lacking both phosphogluconate dehydrogenase and phosphogluconate dehydratase were unable to grow on glycerol, although these strains possessed all of the enzymes needed for degradation of glycerol. These mutants apparently were inhibited by hexosephosphate derivatives, which originated from glycerol-derived triosephosphate and could not be dissimilated. This conclusion was supported by the fact that revertants regaining only a limited capacity to degrade 6-phosphogluconate were glycerol positive but remained glucose negative.

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In Pseudomonas aeruginosa , the transport of glycerol was shown to be genetically controlled and to be dependent on induction by glycerol. Accumulation of 14 C-glycerol was almost completely absent in uninduced cells and in a transport-negative mutant. Kinetic studies with induced cells suggested that glycerol may be transported by two systems with different affinities for glycerol. Osmotically shocked cells did not transport glycerol, and the supernatant fluid from shocked cells contained glycerol-binding activity demonstrable by equilibrium dialysis. The binding protein was not glycerol kinase. Binding activity was absent in shock fluids from the transport-negative mutant and from uninduced cells. The glycerol-binding protein was partially purified by precipitation with ammonium sulfate. Mild heat treatment completely eliminated the binding activity of shock fluid and of the partially purified protein. Sodium azide and N -ethylmaleimide inhibited both transport by whole cells and binding of glycerol by shock fluid. It is concluded that transport of glycerol by P. aeruginosa involves a binding protein responsible for recognition of glycerol and may occur by facilitated diffusion or active transport. A requirement for energy has not been demonstrated.

A study of bacterial flora ill swimming pool water treated with high-free residual chlorine. Am. J. Public Health 47:1101-1109. Rohm and Haas Company. 1956. Improvements in or relating to iodine complexes. British Patent 750,747. Swimming Pool Age. 1961. Swimming pool industry market report. Hoffman-Harris, Inc., New York.

An improved colorimetric assay for carbamyl oxamate, which allows the precise measurement of the activity of oxamic transcarbamylase, has been developed. Activity is maximum over the pH range from 8.3 to 8.7. A cation requirement is satisfied by 2.5 X 10-3 M Mg++ or MnII. The equilibrium constant for the phosphorolysis of carbamyl oxamic acid is 1.6, corresponding to a negative free energy change of-285 cal per mole. The conversion of carbamyl oxamate to oxamate by Streptococcus allantoicus is a unique phosphorolytic reaction catalyzed by oxamic transcarbamylase (Valentine and Wolfe, 1960a; Bojanowski et al., 1962