Structure-guided microbial targeting of antistaphylococcal prodrugs
Abstract
Carboxy ester prodrugs are widely employed to increase oral absorption and potency of phosphonate antibiotics. Prodrugging can mask problematic chemical features that prevent cellular uptake and may enable tissue specific compound delivery. However, many carboxy ester promoieties are rapidly hydrolyzed by serum esterases, limiting their therapeutic potential. While carboxy ester-based prodrug targeting is feasible, it has seen limited use in microbes as microbial esterase specific promoieties have not been described. Here we identify the bacterial esterases, GloB and FrmB, that activate carboxy ester prodrugs in Staphylococcus aureus. Additionally, we determine the substrate specificities for FrmB and GloB and demonstrate the structural basis of these preferences. Finally, we establish the carboxy ester substrate specificities of human and mouse sera, ultimately identifying several promoieties likely to be serum esterase-resistant and microbially labile. These studies will enable structure-guided design of anti-staphylococcal promoieties and expand the range of molecules to target staphylococcal pathogens.
Data availability
Sequencing data and structure data is provided in the manuscript and deposited on the NCBI BioProject database (PRJNA648156) or in the protein data bank (FrmB accession code 7L0A, GloB accession code 7L0B).
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Understanding Staphylococcus aureus resistance to POM-HEXNCBI BioProject database, PRJNA648156.
Article and author information
Author details
Funding
National Institutes of Health (R01 AI103280; R21 AI123808; R21 AI130584)
- Audrey R Odom John
National Center for Research Resources (UL1 RR024992)
- Joseph Jez
Burroughs Wellcome Fund (PATH)
- Audrey R Odom John
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Bavesh D Kana, University of the Witwatersrand, South Africa
Version history
- Preprint posted: December 15, 2020 (view preprint)
- Received: January 18, 2021
- Accepted: July 16, 2021
- Accepted Manuscript published: July 19, 2021 (version 1)
- Version of Record published: July 28, 2021 (version 2)
- Version of Record updated: November 25, 2021 (version 3)
Copyright
© 2021, Miller et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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