Influence of sodium dodecyl sulphate quality on the electrophoretic mobility of the outer membrane proteins of mucoid and non-mucoid Pseudomonas aeruginosa.

The electrophoretic mobilities of proteins F and H1 from the outer membrane of Pseudomonas aeruginosa (mucoid and non-mucoid) in polyacrylamide gel electrophoresis were affected by the quality of sodium dodecyl sulphate (SDS) used. In particular, the sodium tetradecyl sulphate impurity present in crude SDS influenced the mobilities of F and H1. These observations explain conflicting reports on changes in outer membrane proteins with strain and growth conditions. Synthesis of H1 was induced by growth in magnesium depleted medium but repressed when calcium or manganese were added to magnesium depleted medium.