Selecting AMR/MDR Pathogen Surrogates to Identify Genomic Changes Conferring Drug Resistance

The generation of BSL-2 antibiotic-resistant surrogate isolates can greatly enable the screening/testing/validation of effective medical countermeasures against high-risk biothreat pathogens and bypass the regulatory statutes... [ view full abstract ]

The generation of BSL-2 antibiotic-resistant surrogate isolates can greatly enable the screening/testing/validation of effective medical countermeasures against high-risk biothreat pathogens and bypass the regulatory statutes that prevent the intentional creation of antibiotic-resistant BSL-3 agents. While acquisition of functions via horizontal gene transfer can confer antibiotic resistance to susceptible strains, many of these genes are already known and can be readily detected. Multidrug resistance (MDR)-conferring plasmids have also been identified. However, even minor changes in the genome can mediate antibiotic resistance through alternative mechanisms, without the need for gene transfer. These mutations occur naturally and are more difficult to identify and characterize, and are the target of this investigation. In this work, we will generate panels of B. anthracis, F. tularensis, and Y. pestis surrogates that are resistant to single and multiple classes of antibiotics and perform ultra-high-throughput sequencing to characterize their genomic and/or transcriptomic changes. This will help enhance our capability to rapidly detect and generate therapeutics against AMR and MDR pathogens. Furthermore, analysis of the specific mutations that arise from pathogen selection on antibiotics may give insights into novel mechanisms of AMR and MDR.