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bioRxiv · 10.1101/2024.08.02.606422

An engineered prodrug selectively suppresses β-lactam resistant bacteria in a mixed microbial setting

Abstract

The rise of {beta}-lactam resistance necessitates new strategies to combat bacterial infections. We purposefully engineered the {beta}-lactam prodrug AcephPT to exploit {beta}-lactamase activity to selectively suppress resistant bacteria producing extended-spectrum-{beta}-lactamases (ESBLs). Selective targeting of resistant bacteria requires avoiding interaction with penicillin-binding proteins, the conventional targets of {beta}-lactam antibiotics, while maintaining recognition by ESBLs to activate AcephPT only in resistant cells. Computational approaches provide a rationale for structural modifications to the prodrug to achieve this biased activity. We show AcephPT selectively suppresses gram-negative ESBL-producing bacteria in clonal populations and in mixed microbial cultures, with effective selectivity for both lab strains and clinical isolates expressing ESBLs. Time-course NMR experiments confirm hydrolytic activation of AcephPT exclusively by ESBL-producing bacteria. In mixed microbial cultures, AcephPT suppresses proliferation of ESBL-producing strains while sustaining growth of {beta}-lactamase-non-producing bacteria, highlighting its potential to combat {beta}-lactam resistance while promoting antimicrobial stewardship. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=152 SRC="FIGDIR/small/606422v1_ufig1.gif" ALT="Figure 1"> View larger version (62K): org.highwire.dtl.DTLVardef@cd7f9aorg.highwire.dtl.DTLVardef@1747bc6org.highwire.dtl.DTLVardef@6a3419org.highwire.dtl.DTLVardef@825aa6_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Duda, A. M., Ma, H. R., Villalobos, C. A., Kuhn, S. A., He, K., Seay, S. R., Jackson, A. C., Suh, C. M., Puccio, E. A., Anderson, D. A., Fowler, V. G., You, L., Franz, K. J.. 2024-08-03. An engineered prodrug selectively suppresses β-lactam resistant bacteria in a mixed microbial setting. https://doi.org/10.1101/2024.08.02.606422

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