Abstract by Aaron Zaugg
Chemistry and Biochemistry
Proteomic Analysis of Chlorhexidine Resistance in Pseudomonas aeruginosa
Recently, widespread use of chlorhexidine has led to concerns of bacteria developing resistance to chlorhexidine and potentially developing cross resistance with other cationic antimicrobials. We investigated the potential for cross resistance in Gram-negative strains after serial exposure to chlorhexidine and performed a proteomics analysis on the resistant strains to determine potential pathways by which resistance could be aquired. After serial exposure to chlohexidine strains showed decreased suceptibility to collistin, measured by an 8-32 fold increase in minimum inhibitory concentration, but did not show modified resistance to antimicrobial peptides and ceragenins. Proteomic analysis of chlorhexidine-resistant Pseudomonas aeruginosa revealed upregulation in proteins associated with outer membrane biogenesis, chaperones, efflux pumps, flagella, and cell metabolism. Upregulation of several of these proteins have also been correlated to collistin resistance, providing potential links explaining the observed cross resistance.