ABSORPTION AND FLUORESCENCE OF WATER-SOLUBLE PIGMENTS PRODUCED BY FOUR SPECIES OF PSEUDOMONAS.

Pigments produced by four species of Pseudomonas during growth in three media were examined for visible and ultraviolet absorption. Ultraviolet fluorescence excitation and emission spectra were obtained. In all pigments, an absorption maximum occurs at 405 mmu. Ultraviolet excitation of fluorescence occurs primarily at 400 to 410 mmu, with smaller maxima at 460 mmu, or 525 mmu, depending on pH, bacterial species, or medium. Emission maxima, after excitation at 410 mmu, occur at 390 mmu, and 455 to 475 mmu. The differences in fluorescence spectra may be used for taxonomic classification of the Pseudomonas.