Expression of extracellular polysaccharides and proteins by clinical isolates of Pseudomonas aeruginosa in response to environmental conditions.
The opportunistic pathogen Pseudomonas aeruginosa causes chronic respiratory infections in patients with cystic fibrosis (CF). Persistence of this bacterium is attributed to its ability to form biofilms which rely on an extracellular polymeric substance matrix. Extracellular polysaccharides (EPS) and secreted proteins are key matrix components of P. aeruginosa biofilms. Recently, nebulized magnesium sulfate has been reported as a significant bronchodilator for asthmatic patients including CF. However, the impact of magnesium sulfate on the virulence effect of P. aeruginosa is lacking. In this report, we investigated the influence of magnesium sulfate and other environmental factors on the synthesis of alginate and secretion of proteins by a mucoid and a non-mucoid strain of P. aeruginosa, respectively. By applying the Plackett-Burman and Box-Behnken experimental designs, we found that phosphates (6.0 g/l), ammonium sulfate (4.0 g/l), and trace elements (0.6 mg/l) markedly supported alginate production by the mucoid strain. However, ferrous sulfate (0.3 mg/l), magnesium sulfate (0.02 g/l), and phosphates (6.0 g/l) reinforced the secretion of proteins by the non-mucoid strain.
['Lotfy|Walid A|WA|', 'Atalla|Ramy G|RG|', 'Sabra|Wael A|WA|', 'El-Helow|Ehab R|ER|']
D000464:Alginates D001426:Bacterial Proteins D001993:Bronchodilator Agents D004781:Environmental Exposure D015870:Gene Expression D006801:Humans D010710:Phosphates D011552:Pseudomonas Infections D011550:Pseudomonas aeruginosa D013431:Sulfates
Polysaccharides Proteins Pseudomonas aeruginosa Alginate