Zinc eluted from siliconized latex urinary catheters decreases OprD expression, causing carbapenem resistance in Pseudomonas aeruginosa

Abstract

The activities of carbapenems against Pseudomonas aeruginosa decreased in the presence of siliconized latex urinary catheters (SLUCs). This effect was associated with the loss of OprD. The zinc that eluted from SLUCs is responsible for this phenomenon. We have found that zinc exerts a negative effect on the expression of OprD, the porin responsible for carbapenem entry into P. aeruginosa.

FIG. 1.

SDS-PAGE showing OMP profiles of P. aeruginosa grown in MH (lanes 2 and 5), eluates from SLUCs (lanes 3 and 6), and zinc-supplemented MH (final zinc concentration, 36.8 μg/ml) (lanes 4 and 7). Lanes: 1, molecular weight markers; 2 to 4, OMP profile of PAO1; 5 to 7, OMP profile of OprD-negative PAO1. White arrow, OprD2; black arrow, OprD3. Numbers on the left are in kilodaltons.