Fig. 4
Effect of low-temperature stress on the expression of efflux pump, porin, and β-lactamase encoding genes in A. baumannii. Gene expression encoding efflux pumps (adeJ and adeB), porin (ompA), and β-lactamase (oxa-51 and oxa-23) was analyzed in A. baumannii ATCC19606 and eight clinical isolates. These isolates included four MEMR isolates carrying oxa-23 and four MEMNR isolates. Nine strains of A. baumannii underwent 16 h at 4 °C. The relative levels of expression of genes (versus 37 °C) for each tested strain are presented as the mean of n = 3 independent experiments