Electrochemical Detection of Tobramycin Resistance in Pseudomonas Aeruginosa

Pseudomonas aeruginosa are Gram-negative anaerobic bacteria and is listedby the World Health Organization as one of the critical antibiotic-resistant pathogens1. The treatment for P. aeruginosa infection can be challenging, since this pathogen often exhibits an enhanced resistance to antibiotics, including aminoglycosides, such as Tobramycin (TOB). These are called mucoid strains and are mainly found in the lungs of cystic fibrosis patients, where it is a common cause of death for these individuals2. The overall goal of the presented work is the development of an electrochemical method capable of detecting TOB uptake in P. aeruginosa. Drug susceptible and drug resistant strains of P. aeruginosa were exposed to a TOB solution for different time intervals (Figure 1). By removing organisms from the solution after incubation, the remaining TOB in solution can be determined by electrochemistry. Resistant bacteria strains showed significantly lower TOB uptake than susceptible organisms, because cellular drug resistant mechanisms enable them to inhibit TOB absorption. The presented drug uptake studies demonstrate the sensitivity of electrochemistry to detect drug resistance in living bacteria. References Singh, M., Yau, Y. C. W., Wang, S., Waters, V. & Kumar, A. MexXY efflux pump overexpression and aminoglycoside resistance in cystic fibrosis isolates of pseudomonas aeruginosa from chronic infections. Canadian Journal of Microbiology 63, 929–938 (2017). Germoni, L. A. P., Bremer, P. J. & Lamont, I. L. The effect of alginate lyase on the gentamicin resistance of Pseudomonas aeruginosa in mucoid biofilms. Journal of Applied Microbiology 121, 126–135 (2016). Figure 1