MORPHOLOGICAL AND PHYSIOLOGICAL CONSIDERATIONS OF COLONIAL VARIANTS OF PSEUDOMONAS AERUGINOSA

Abstract

Marked differences exist in colonial morphology between the smooth state, the mucoid state, and the filamentous variant of P. aeruginosa. The cellular morphology showed correlative differences between variants. Filamentous cells varied in length from 4 [mu] to filamentous structures in excess of 300 [mu] while the smooth and mucoid cells measured 1.5-2.0 [mu] long by 0.5 [mu] wide. Another differential characteristic was the absence of flagella on filamentous cells. Capsules were demonstrated around cells of the mucoid state but not around smooth and filamentous cells. Filamentous cells utilized glucose, arabinose, galactose, and xylose, giving an average final pH of 4.4. Smooth cells produced acid from glucose, galactose, and xylose, giving an average final pH of 4.7. Mucoid cells attacked only glucose and xylose, giving an average final pH of 5.6. Mucoid cells were slightly more pathogenic for albino mice than the smooth cells but markedly more toxic than cells of the filamentous variant.