@ARTICLE{10.3389/fmicb.2021.562157, AUTHOR={Elder, Felicity C. T. and Feil, Edward J. and Pascoe, Ben and Sheppard, Samuel K. and Snape, Jason and Gaze, William H. and Kasprzyk-Hordern, Barbara}, TITLE={Stereoselective Bacterial Metabolism of Antibiotics in Environmental Bacteria – A Novel Biochemical Workflow}, JOURNAL={Frontiers in Microbiology}, VOLUME={12}, YEAR={2021}, URL={https://www.frontiersin.org/articles/10.3389/fmicb.2021.562157}, DOI={10.3389/fmicb.2021.562157}, ISSN={1664-302X}, ABSTRACT={Although molecular genetic approaches have greatly increased our understanding of the evolution and spread of antibiotic resistance genes, there are fewer studies on the dynamics of antibiotic – bacterial (A-B) interactions, especially with respect to stereochemistry. Addressing this knowledge gap requires an interdisciplinary synthesis, and the development of sensitive and selective analytical tools. Here we describe SAM (stereoselective antimicrobial metabolism) workflow, a novel interdisciplinary approach for assessing bacterial resistance mechanisms in the context of A-B interactions that utilise a combination of whole genome sequencing and mass spectrometry. Chloramphenicol was used to provide proof-of-concept to demonstrate the importance of stereoselective metabolism by resistant environmental bacteria. Our data shows that chloramphenicol can be stereoselectively transformed via microbial metabolism with R,R-(-)-CAP being subject to extensive metabolic transformation by an environmental bacterial strain. In contrast S,S-(+)-CAP is not metabolised by this bacterial strain, possibly due to the lack of previous exposure to this isomer in the absence of historical selective pressure to evolve metabolic capacity.} }