Production and Characterization of the Slime Polysaccharide of Pseudomonas aeruginosa

Abstract

The slime polysaccharides produced by Pseudomonas aeruginosa isolated from a variety of human infections were investigated. Slime production in culture seemed optimal when adequate amounts of carbohydrate were present and under conditions of either high osmotic pressure or inadequate protein supply. The polysaccharides produced by the organisms were similar to each other, to the slime of Azotobacter vinelandii, and to seaweed alginic acids. They were composed of p3-1, 4-linked D-mannuronic acid residues and variable amounts of its 5-epimer L-guluronic acid. All bacterial polymers contained o-acetyl groups which are absent in the alginates. The polysaccharides differed considerably in the ratio of mannuronic to guluronic acid content and in the number of o-acetyl groups. The particular composition of the slime was not found to be characteristic for the disease process from which the mucoid variants of P. aeruginosa were obtained. Polysaccharides isolated from organisms obtained from different patients were similar, but varied somewhat in composition, IR spectra, and effects of alkali treatment. These polysaccharides were quite similar, but not identical, to alginic acid. The significance of these differences in terms of structures or relation to a particular source is not clear. Also, data (9) suggest that the polysaccharide produced by organisms from cystic fibrosis patients may 915

Influence of nutrient media on the chemical composition of the exopolysaccharide from mucoid and non-mucoid Pseudomonas aeruginosa

“…A salient feature of the P. aeruginosa EPS is its heterogeneity based upon the clinical origin of the strains. The results of the present study sup-port and extend previous studies which show that Pseudomonas EPS is structurally similar to alginate produced by several species of marine algae [3], except that seaweed alginate was not acetylated. In addition, our data demonstrate that the extracellular material produced by strains of P. aeruginosa from patients with or without CF was composed mainly of alginate, except in the nonmucoid isolate from the bronchiectasic patient.…”

“…Other experiments also showed the heterogeneity of the alginates produced by mucoid P. aeruginosa from patients with or without CF [3,7,8,12]. Comparison of our data with these studies is not easy because of differences in the bacterial growth, variability in the EPS extraction and the chemical analyses; however, authors using identical analytical methods have found a similar composition of the alginate produced by mucoid isolates of P. aeruginosa from patients with or without CF [9,23].…”

“…The initial infecting P. aeruginosa are typically non-mucoid; however, upon continued exposure to the CF lung environment, they become highly mucoid [2]. These mucoid strains of P. aeruginosa produce a polyanionic exopolysaccharide (EPS) which resembles alginic acid in chemical composition [3]. Alginate produced by P. aeruginosa is an acetylated exopolysaccharide composed of 1,4-1inked D-mannuronic acid and L-guluronic acid [4].…”

Matrix composition and community structure analysis of a novel bacterial pyrite leaching community

“…The EPS was purified according to Evans and Linker (1973). The purified EPS was then sent for carbohydrate analysis to the Complex Carbohydrate Research Center of the University of Georgia (USA).…”

Nonmucoid conversion of mucoidPseudomonas aeruginosainduced by sulfate-stimulated growth

“…In chronic CF airways, P. aeruginosa strains that have acquired selected phenotypes are recovered and such phenotypic changes are induced for survival in the harsh environment of the human lung (Burns et al, 2001;Hogardt et al, 2007;Mena et al, 2008). One of these changes is an overproduction of a capsule-like polysaccharide called alginate (Evans & Linker, 1973). Mucoid P. aeruginosa strains isolated from sputum of CF patients have a mutation in the mucA gene, encoding MucA, a negative regulator of AlgT that activates transcription of the alginate biosynthesis operon (Martin et al, 1993).…”