TEMPERATURE-DEPENDENT PROTEIN AND LIPOPOLYSACCHARIDE EXPRESSION IN CLINICAL AEROMONAS ISOLATES

Clinical isolates of Aeromonas were grown at eight different temperatu res from 10 degrees C to 40 degrees C. Whole cell lysates were examine d by SDS-PAGE and major temperature-dependent changes to both protein and lipopolysaccharide (LPS) profiles were identified. Cells grown at the higher temperatures (37 degrees C and 40 degrees C) produced abund antly a protein of c. 60 kDa which was not detected at the lower tempe ratures. Temperature-dependent expressions of other proteins were also noted but these were more variable among the isolates. An effect of t emperature on expression of lipopolysaccharides was also noted in that some strains produced significantly less O-polysaccharides at the hig her temperatures. After fractionation of cells, major differences in t he expression of cell envelope and outer-membrane proteins between cel ls grown at low and high temperatures were noted although no unifying patterns could be discerned. Such growth temperature-induced changes i n the cell envelope constituents have not been described previously fo r Aeromonas isolates from man.