Poochit Nonejuie, Ph.D.
In the past decades, increasing number of multidrug resistant (MDR) bacteria infection in hospitals has been documented worldwide. The wide spread of multidrug-resistant (MDR) Enterococcus spp., Staphylococcus aureus, Klebsiella spp., Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp., called “ESKAPE” is among the most concerned. Recent studies showed that some MDR Gram-negative pathogens are now resistant to all antibiotics available in the market. Even though there are some new antibiotics approved by FDA recently, they only work against Gram-positive bacteria. The combination of the drug resistance and the lack of new antibiotics make millions of lives be at risk from MDR Gram-negative pathogen infection. Thus, novel antibiotics are strongly needed in order to put MDR Gram-negative pathogen at bay. However, the search of antibiotics for Gram-negative is far more difficult than that for Gram-positive due to its outermembrane (OM) which provides an extra barrier against antibiotic penetration. Therefore, potentiator mechanism of action on OM is also crucial to antibiotic discovery.
Our lab is focused on two related areas of antibiotic research. First, we aim to use a newly developed technique, bacterial cytological profiling (BCP), as the method for developing the discovery platform specific to certain Gram-negative pathogen such as A. baumannii. By having species-specific discovery platforms, we hope to increase the chance of finding new antibiotics against specific pathogens and reduce the drug effect to other commensal bacteria. Second, we aim to study the mechanism underlying OM disruption by some antibacterial molecules and potentiators. We believe that understanding OM disruption mechanism by potentiators will help researchers select and explore more compounds that are commonly neglected by other conventional screening methods due to the compounds’ negative killing result against Gram-negative bacteria.