Scientists Test New Method for Combatting Antimicrobial Resistance

To combat antimicrobial resistance, scientists from the University of Washington are using a high-throughput method for cultivation and lipidomic analysis for antimicrobial resistant bacteria (1). The study, published in the journal of Analytical and Bioanalytical Chemistry, outlined how this method was developed for standard 96-well plates exemplified by methicillin-resistant Staphylococcus aureus (MRSA).

Staphylococcus aureus | Image Credit: © Tatiana Shepeleva - stock.adobe.com

Antimicrobial resistance kills at least 1.27 million people worldwide and was associated with 5 million deaths in 2019, according to the Centers for Disease Control and Prevention (2). This represents a public health crisis that scientists and healthcare providers alike are working to combat.

There is a need to develop more effective methods to analyze antimicrobial resistant bacteria. Many of the methods that currently exist for analysis use high-throughput lipidomics for bacterial phenotyping, which allows researchers to unveil lipid-mediated pathways when dealing with several strains of a disease (1). However, these systems require bacterial cultivation on a large scale, which do not allow for bioassays that are typically used in 96-well plates, such as susceptibility tests, growth curve measurements, and biofilm quantitation. For this study, the scientists created their own means of cultivating and analyzing antimicrobial-resistant bacteria, which was done by combining a 30-mm liquid chromatography (LC) column with ion mobility (IM) separation.

To test this system, the scientists developed it for standard 96-well plates exemplified by methicillin-resistant Staphylococcus aureus (MRSA). The system allowed elution times to be shortened to 3.6 min for a single LC run, all without losing major lipid features, while the IM dimension largely rescue the peak capacity of samples. Through multi-linear calibration, it was found that retention time deviation could be limited to within 5%, making database-based automatic lipid identification feasible. The system was tested further by characterizing lipidomic phenotypes of antimicrobial-resistant mutants derived from the MRSA strain, W308, which were also grown in a 96-well plate.

Reference

(1) Zhang, R.; Ashford, N.K.; Li, A.; Ross, D. H.; Werth, B. J.; Xu, L. High-throughput analysis of lipidomic phenotypes of methicillin-resistant Staphylococcus aureus by coupling in situ 96-well cultivation and HILIC-ion mobility-mass spectrometry. Anal. Bioanal. Chem. 2023. DOI: https://doi.org/10.1007/s00216-023-04890-6

(2) Centers for Disease Control and Prevention. About Antimicrobial Resistance. U.S. Department of Health & Human Services 2023. https://www.cdc.gov/drugresistance/about.html (accessed 2023-09-06)