PIGMENT PRODUCTION BY PSEUDOMONAS AERUGINOSA ON GLUTAMIC ACID MEDIUM

II. STUDIES ON FLUORESCENCE I

Abstract

1) The fluorescent substance produced by Pseudomonas aeruginosa was studied using strains which possess a charcteristic pigment-producing ability, strains No. 134, 145 and 117.
2) The Fluorescence I production of strain No. 134 is rapid and pronounced.
The effect of pH on the yellow-green portion of the Fluorescence I of this strain was studied and the following results were obserbed:
i) A reversible change in the tone of fluorescence takes place between pH 5.0 and pH 10.0. The color changes from blue to yellow-green at about pH 7.5 with a clear demarcation.
ii) The absorption spectrum of the substance shows a peak at 400mμ, and a characteristic wave length shows a peak at 460mμ. A change is noted in the absorption spectrum and characteristic wave length at about pH 5.0-4.0 when the tone of the fluorescence changes from colorless to orange.
3) The Fluorescence I fraction obtained by gel filtration from the culture filtrate of the three strains grown on the glutamic acid medium was examined paper-electrophoretically and the following results were obtained:
i) Four fluorescent spots appear on the filter paper. The spots were arbitrarily called α, β, γ and δ from the negative pole side. Strain 117 shows α and β and strains 134 and 145 shows β, γ and δ
ii) These spots appear in order from the negative pole side with time of cultivation regardless of the strain.