Absorption and Fluorescence of Water-Soluble Pigments Produced by Four Species of Pseudomonas

Abstract

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 mμ. Ultraviolet excitation of fluorescence occurs primarily at 400 to 410 mμ, with smaller maxima at 460 mμ, or 525 mμ, depending on p H, bacterial species, or medium. Emission maxima, after excitation at 410 mμ, occur at 390 mμ, and 455 to 475 mμ. The differences in fluorescence spectra may be used for taxonomic classification of the Pseudomonas .